| Thomas Wouters | 1b7f891 | 2007-09-19 03:06:30 +0000 | [diff] [blame] | 1 | ------------------------------------------------------------------------
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 | 2 | -- ddSubtract.decTest -- decDouble subtraction                        --
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| Benjamin Peterson | f17ff4e | 2008-07-31 16:32:12 +0000 | [diff] [blame] | 3 | -- Copyright (c) IBM Corporation, 1981, 2008.  All rights reserved.   --
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| Thomas Wouters | 1b7f891 | 2007-09-19 03:06:30 +0000 | [diff] [blame] | 4 | ------------------------------------------------------------------------
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 | 5 | -- Please see the document "General Decimal Arithmetic Testcases"     --
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 | 6 | -- at http://www2.hursley.ibm.com/decimal for the description of      --
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 | 7 | -- these testcases.                                                   --
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 | 8 | --                                                                    --
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 | 9 | -- These testcases are experimental ('beta' versions), and they       --
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 | 10 | -- may contain errors.  They are offered on an as-is basis.  In       --
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 | 11 | -- particular, achieving the same results as the tests here is not    --
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 | 12 | -- a guarantee that an implementation complies with any Standard      --
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 | 13 | -- or specification.  The tests are not exhaustive.                   --
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 | 14 | --                                                                    --
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 | 15 | -- Please send comments, suggestions, and corrections to the author:  --
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 | 16 | --   Mike Cowlishaw, IBM Fellow                                       --
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 | 17 | --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
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 | 18 | --   mfc@uk.ibm.com                                                   --
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 | 19 | ------------------------------------------------------------------------
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| Mark Dickinson | 8a54653 | 2009-10-08 16:30:38 +0000 | [diff] [blame] | 20 | version: 2.59
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| Thomas Wouters | 1b7f891 | 2007-09-19 03:06:30 +0000 | [diff] [blame] | 21 | 
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 | 22 | -- This set of tests are for decDoubles only; all arguments are
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 | 23 | -- representable in a decDouble
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 | 24 | precision:   16
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 | 25 | maxExponent: 384
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 | 26 | minExponent: -383
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 | 27 | extended:    1
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 | 28 | clamp:       1
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 | 29 | rounding:    half_even
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 | 30 | 
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 | 31 | -- [first group are 'quick confidence check']
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 | 32 | ddsub001 subtract  0   0  -> '0'
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 | 33 | ddsub002 subtract  1   1  -> '0'
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 | 34 | ddsub003 subtract  1   2  -> '-1'
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 | 35 | ddsub004 subtract  2   1  -> '1'
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 | 36 | ddsub005 subtract  2   2  -> '0'
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 | 37 | ddsub006 subtract  3   2  -> '1'
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 | 38 | ddsub007 subtract  2   3  -> '-1'
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 | 39 | 
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 | 40 | ddsub011 subtract -0   0  -> '-0'
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 | 41 | ddsub012 subtract -1   1  -> '-2'
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 | 42 | ddsub013 subtract -1   2  -> '-3'
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 | 43 | ddsub014 subtract -2   1  -> '-3'
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 | 44 | ddsub015 subtract -2   2  -> '-4'
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 | 45 | ddsub016 subtract -3   2  -> '-5'
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 | 46 | ddsub017 subtract -2   3  -> '-5'
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 | 47 | 
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 | 48 | ddsub021 subtract  0  -0  -> '0'
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 | 49 | ddsub022 subtract  1  -1  -> '2'
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 | 50 | ddsub023 subtract  1  -2  -> '3'
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 | 51 | ddsub024 subtract  2  -1  -> '3'
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 | 52 | ddsub025 subtract  2  -2  -> '4'
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 | 53 | ddsub026 subtract  3  -2  -> '5'
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 | 54 | ddsub027 subtract  2  -3  -> '5'
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 | 55 | 
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 | 56 | ddsub030 subtract  11  1  -> 10
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 | 57 | ddsub031 subtract  10  1  ->  9
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 | 58 | ddsub032 subtract  9   1  ->  8
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 | 59 | ddsub033 subtract  1   1  ->  0
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 | 60 | ddsub034 subtract  0   1  -> -1
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 | 61 | ddsub035 subtract -1   1  -> -2
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 | 62 | ddsub036 subtract -9   1  -> -10
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 | 63 | ddsub037 subtract -10  1  -> -11
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 | 64 | ddsub038 subtract -11  1  -> -12
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 | 65 | 
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 | 66 | ddsub040 subtract '5.75' '3.3'  -> '2.45'
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 | 67 | ddsub041 subtract '5'    '-3'   -> '8'
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 | 68 | ddsub042 subtract '-5'   '-3'   -> '-2'
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 | 69 | ddsub043 subtract '-7'   '2.5'  -> '-9.5'
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 | 70 | ddsub044 subtract '0.7'  '0.3'  -> '0.4'
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 | 71 | ddsub045 subtract '1.3'  '0.3'  -> '1.0'
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 | 72 | ddsub046 subtract '1.25' '1.25' -> '0.00'
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 | 73 | 
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 | 74 | ddsub050 subtract '1.23456789'    '1.00000000' -> '0.23456789'
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 | 75 | ddsub051 subtract '1.23456789'    '1.00000089' -> '0.23456700'
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 | 76 | 
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 | 77 | ddsub060 subtract '70'    '10000e+16' -> '-1.000000000000000E+20' Inexact Rounded
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 | 78 | ddsub061 subtract '700'    '10000e+16' -> '-1.000000000000000E+20' Inexact Rounded
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 | 79 | ddsub062 subtract '7000'    '10000e+16' -> '-9.999999999999999E+19' Inexact Rounded
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 | 80 | ddsub063 subtract '70000'    '10000e+16' -> '-9.999999999999993E+19' Rounded
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 | 81 | ddsub064 subtract '700000'    '10000e+16' -> '-9.999999999999930E+19' Rounded
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 | 82 |   -- symmetry:
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 | 83 | ddsub065 subtract '10000e+16'    '70' -> '1.000000000000000E+20' Inexact Rounded
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 | 84 | ddsub066 subtract '10000e+16'    '700' -> '1.000000000000000E+20' Inexact Rounded
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 | 85 | ddsub067 subtract '10000e+16'    '7000' -> '9.999999999999999E+19' Inexact Rounded
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 | 86 | ddsub068 subtract '10000e+16'    '70000' -> '9.999999999999993E+19' Rounded
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 | 87 | ddsub069 subtract '10000e+16'    '700000' -> '9.999999999999930E+19' Rounded
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 | 88 | 
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 | 89 |   -- some of the next group are really constructor tests
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 | 90 | ddsub090 subtract '00.0'    '0.0'  -> '0.0'
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 | 91 | ddsub091 subtract '00.0'    '0.00' -> '0.00'
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 | 92 | ddsub092 subtract '0.00'    '00.0' -> '0.00'
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 | 93 | ddsub093 subtract '00.0'    '0.00' -> '0.00'
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 | 94 | ddsub094 subtract '0.00'    '00.0' -> '0.00'
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 | 95 | ddsub095 subtract '3'    '.3'   -> '2.7'
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 | 96 | ddsub096 subtract '3.'   '.3'   -> '2.7'
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 | 97 | ddsub097 subtract '3.0'  '.3'   -> '2.7'
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 | 98 | ddsub098 subtract '3.00' '.3'   -> '2.70'
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 | 99 | ddsub099 subtract '3'    '3'    -> '0'
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 | 100 | ddsub100 subtract '3'    '+3'   -> '0'
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 | 101 | ddsub101 subtract '3'    '-3'   -> '6'
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 | 102 | ddsub102 subtract '3'    '0.3'  -> '2.7'
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 | 103 | ddsub103 subtract '3.'   '0.3'  -> '2.7'
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 | 104 | ddsub104 subtract '3.0'  '0.3'  -> '2.7'
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 | 105 | ddsub105 subtract '3.00' '0.3'  -> '2.70'
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 | 106 | ddsub106 subtract '3'    '3.0'  -> '0.0'
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 | 107 | ddsub107 subtract '3'    '+3.0' -> '0.0'
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 | 108 | ddsub108 subtract '3'    '-3.0' -> '6.0'
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 | 109 | 
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 | 110 | -- the above all from add; massaged and extended.  Now some new ones...
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 | 111 | -- [particularly important for comparisons]
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 | 112 | -- NB: -xE-8 below were non-exponents pre-ANSI X3-274, and -1E-7 or 0E-7
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 | 113 | -- with input rounding.
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 | 114 | ddsub120 subtract  '10.23456784'    '10.23456789'  -> '-5E-8'
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 | 115 | ddsub121 subtract  '10.23456785'    '10.23456789'  -> '-4E-8'
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 | 116 | ddsub122 subtract  '10.23456786'    '10.23456789'  -> '-3E-8'
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 | 117 | ddsub123 subtract  '10.23456787'    '10.23456789'  -> '-2E-8'
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 | 118 | ddsub124 subtract  '10.23456788'    '10.23456789'  -> '-1E-8'
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 | 119 | ddsub125 subtract  '10.23456789'    '10.23456789'  -> '0E-8'
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 | 120 | ddsub126 subtract  '10.23456790'    '10.23456789'  -> '1E-8'
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 | 121 | ddsub127 subtract  '10.23456791'    '10.23456789'  -> '2E-8'
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 | 122 | ddsub128 subtract  '10.23456792'    '10.23456789'  -> '3E-8'
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 | 123 | ddsub129 subtract  '10.23456793'    '10.23456789'  -> '4E-8'
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 | 124 | ddsub130 subtract  '10.23456794'    '10.23456789'  -> '5E-8'
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 | 125 | ddsub131 subtract  '10.23456781'    '10.23456786'  -> '-5E-8'
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 | 126 | ddsub132 subtract  '10.23456782'    '10.23456786'  -> '-4E-8'
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 | 127 | ddsub133 subtract  '10.23456783'    '10.23456786'  -> '-3E-8'
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 | 128 | ddsub134 subtract  '10.23456784'    '10.23456786'  -> '-2E-8'
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 | 129 | ddsub135 subtract  '10.23456785'    '10.23456786'  -> '-1E-8'
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 | 130 | ddsub136 subtract  '10.23456786'    '10.23456786'  -> '0E-8'
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 | 131 | ddsub137 subtract  '10.23456787'    '10.23456786'  -> '1E-8'
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 | 132 | ddsub138 subtract  '10.23456788'    '10.23456786'  -> '2E-8'
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 | 133 | ddsub139 subtract  '10.23456789'    '10.23456786'  -> '3E-8'
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 | 134 | ddsub140 subtract  '10.23456790'    '10.23456786'  -> '4E-8'
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 | 135 | ddsub141 subtract  '10.23456791'    '10.23456786'  -> '5E-8'
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 | 136 | ddsub142 subtract  '1'              '0.999999999'  -> '1E-9'
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 | 137 | ddsub143 subtract  '0.999999999'    '1'            -> '-1E-9'
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 | 138 | ddsub144 subtract  '-10.23456780'   '-10.23456786' -> '6E-8'
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 | 139 | ddsub145 subtract  '-10.23456790'   '-10.23456786' -> '-4E-8'
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 | 140 | ddsub146 subtract  '-10.23456791'   '-10.23456786' -> '-5E-8'
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 | 141 | 
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 | 142 | -- additional scaled arithmetic tests [0.97 problem]
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 | 143 | ddsub160 subtract '0'     '.1'      -> '-0.1'
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 | 144 | ddsub161 subtract '00'    '.97983'  -> '-0.97983'
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 | 145 | ddsub162 subtract '0'     '.9'      -> '-0.9'
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 | 146 | ddsub163 subtract '0'     '0.102'   -> '-0.102'
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 | 147 | ddsub164 subtract '0'     '.4'      -> '-0.4'
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 | 148 | ddsub165 subtract '0'     '.307'    -> '-0.307'
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 | 149 | ddsub166 subtract '0'     '.43822'  -> '-0.43822'
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 | 150 | ddsub167 subtract '0'     '.911'    -> '-0.911'
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 | 151 | ddsub168 subtract '.0'    '.02'     -> '-0.02'
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 | 152 | ddsub169 subtract '00'    '.392'    -> '-0.392'
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 | 153 | ddsub170 subtract '0'     '.26'     -> '-0.26'
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 | 154 | ddsub171 subtract '0'     '0.51'    -> '-0.51'
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 | 155 | ddsub172 subtract '0'     '.2234'   -> '-0.2234'
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 | 156 | ddsub173 subtract '0'     '.2'      -> '-0.2'
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 | 157 | ddsub174 subtract '.0'    '.0008'   -> '-0.0008'
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 | 158 | -- 0. on left
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 | 159 | ddsub180 subtract '0.0'     '-.1'      -> '0.1'
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 | 160 | ddsub181 subtract '0.00'    '-.97983'  -> '0.97983'
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 | 161 | ddsub182 subtract '0.0'     '-.9'      -> '0.9'
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 | 162 | ddsub183 subtract '0.0'     '-0.102'   -> '0.102'
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 | 163 | ddsub184 subtract '0.0'     '-.4'      -> '0.4'
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 | 164 | ddsub185 subtract '0.0'     '-.307'    -> '0.307'
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 | 165 | ddsub186 subtract '0.0'     '-.43822'  -> '0.43822'
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 | 166 | ddsub187 subtract '0.0'     '-.911'    -> '0.911'
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 | 167 | ddsub188 subtract '0.0'     '-.02'     -> '0.02'
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 | 168 | ddsub189 subtract '0.00'    '-.392'    -> '0.392'
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 | 169 | ddsub190 subtract '0.0'     '-.26'     -> '0.26'
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 | 170 | ddsub191 subtract '0.0'     '-0.51'    -> '0.51'
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 | 171 | ddsub192 subtract '0.0'     '-.2234'   -> '0.2234'
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 | 172 | ddsub193 subtract '0.0'     '-.2'      -> '0.2'
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 | 173 | ddsub194 subtract '0.0'     '-.0008'   -> '0.0008'
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 | 174 | -- negatives of same
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 | 175 | ddsub200 subtract '0'     '-.1'      -> '0.1'
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 | 176 | ddsub201 subtract '00'    '-.97983'  -> '0.97983'
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 | 177 | ddsub202 subtract '0'     '-.9'      -> '0.9'
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 | 178 | ddsub203 subtract '0'     '-0.102'   -> '0.102'
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 | 179 | ddsub204 subtract '0'     '-.4'      -> '0.4'
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 | 180 | ddsub205 subtract '0'     '-.307'    -> '0.307'
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 | 181 | ddsub206 subtract '0'     '-.43822'  -> '0.43822'
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 | 182 | ddsub207 subtract '0'     '-.911'    -> '0.911'
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 | 183 | ddsub208 subtract '.0'    '-.02'     -> '0.02'
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 | 184 | ddsub209 subtract '00'    '-.392'    -> '0.392'
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 | 185 | ddsub210 subtract '0'     '-.26'     -> '0.26'
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 | 186 | ddsub211 subtract '0'     '-0.51'    -> '0.51'
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 | 187 | ddsub212 subtract '0'     '-.2234'   -> '0.2234'
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 | 188 | ddsub213 subtract '0'     '-.2'      -> '0.2'
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 | 189 | ddsub214 subtract '.0'    '-.0008'   -> '0.0008'
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 | 190 | 
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 | 191 | -- more fixed, LHS swaps [really the same as testcases under add]
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 | 192 | ddsub220 subtract '-56267E-12' 0  -> '-5.6267E-8'
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 | 193 | ddsub221 subtract '-56267E-11' 0  -> '-5.6267E-7'
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 | 194 | ddsub222 subtract '-56267E-10' 0  -> '-0.0000056267'
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 | 195 | ddsub223 subtract '-56267E-9'  0  -> '-0.000056267'
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 | 196 | ddsub224 subtract '-56267E-8'  0  -> '-0.00056267'
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 | 197 | ddsub225 subtract '-56267E-7'  0  -> '-0.0056267'
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 | 198 | ddsub226 subtract '-56267E-6'  0  -> '-0.056267'
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 | 199 | ddsub227 subtract '-56267E-5'  0  -> '-0.56267'
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 | 200 | ddsub228 subtract '-56267E-2'  0  -> '-562.67'
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 | 201 | ddsub229 subtract '-56267E-1'  0  -> '-5626.7'
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 | 202 | ddsub230 subtract '-56267E-0'  0  -> '-56267'
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 | 203 | -- symmetry ...
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 | 204 | ddsub240 subtract 0 '-56267E-12'  -> '5.6267E-8'
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 | 205 | ddsub241 subtract 0 '-56267E-11'  -> '5.6267E-7'
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 | 206 | ddsub242 subtract 0 '-56267E-10'  -> '0.0000056267'
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 | 207 | ddsub243 subtract 0 '-56267E-9'   -> '0.000056267'
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 | 208 | ddsub244 subtract 0 '-56267E-8'   -> '0.00056267'
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 | 209 | ddsub245 subtract 0 '-56267E-7'   -> '0.0056267'
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 | 210 | ddsub246 subtract 0 '-56267E-6'   -> '0.056267'
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 | 211 | ddsub247 subtract 0 '-56267E-5'   -> '0.56267'
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 | 212 | ddsub248 subtract 0 '-56267E-2'   -> '562.67'
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 | 213 | ddsub249 subtract 0 '-56267E-1'   -> '5626.7'
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 | 214 | ddsub250 subtract 0 '-56267E-0'   -> '56267'
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 | 215 | 
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 | 216 | -- now some more from the 'new' add
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 | 217 | ddsub301 subtract '1.23456789'  '1.00000000' -> '0.23456789'
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 | 218 | ddsub302 subtract '1.23456789'  '1.00000011' -> '0.23456778'
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 | 219 | 
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 | 220 | -- some carrying effects
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 | 221 | ddsub321 subtract '0.9998'  '0.0000' -> '0.9998'
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 | 222 | ddsub322 subtract '0.9998'  '0.0001' -> '0.9997'
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 | 223 | ddsub323 subtract '0.9998'  '0.0002' -> '0.9996'
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 | 224 | ddsub324 subtract '0.9998'  '0.0003' -> '0.9995'
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 | 225 | ddsub325 subtract '0.9998'  '-0.0000' -> '0.9998'
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 | 226 | ddsub326 subtract '0.9998'  '-0.0001' -> '0.9999'
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 | 227 | ddsub327 subtract '0.9998'  '-0.0002' -> '1.0000'
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 | 228 | ddsub328 subtract '0.9998'  '-0.0003' -> '1.0001'
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 | 229 | 
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 | 230 | -- internal boundaries
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 | 231 | ddsub346 subtract '10000e+9'  '7'   -> '9999999999993'
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 | 232 | ddsub347 subtract '10000e+9'  '70'   -> '9999999999930'
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 | 233 | ddsub348 subtract '10000e+9'  '700'   -> '9999999999300'
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 | 234 | ddsub349 subtract '10000e+9'  '7000'   -> '9999999993000'
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 | 235 | ddsub350 subtract '10000e+9'  '70000'   -> '9999999930000'
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 | 236 | ddsub351 subtract '10000e+9'  '700000'   -> '9999999300000'
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 | 237 | ddsub352 subtract '7' '10000e+9'   -> '-9999999999993'
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 | 238 | ddsub353 subtract '70' '10000e+9'   -> '-9999999999930'
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 | 239 | ddsub354 subtract '700' '10000e+9'   -> '-9999999999300'
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 | 240 | ddsub355 subtract '7000' '10000e+9'   -> '-9999999993000'
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 | 241 | ddsub356 subtract '70000' '10000e+9'   -> '-9999999930000'
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 | 242 | ddsub357 subtract '700000' '10000e+9'   -> '-9999999300000'
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 | 243 | 
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 | 244 | -- zero preservation
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 | 245 | ddsub361 subtract 1 '0.0001' -> '0.9999'
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 | 246 | ddsub362 subtract 1 '0.00001' -> '0.99999'
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 | 247 | ddsub363 subtract 1 '0.000001' -> '0.999999'
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 | 248 | ddsub364 subtract 1 '0.0000000000000001' -> '0.9999999999999999'
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 | 249 | ddsub365 subtract 1 '0.00000000000000001' -> '1.000000000000000' Inexact Rounded
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 | 250 | ddsub366 subtract 1 '0.000000000000000001' -> '1.000000000000000' Inexact Rounded
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 | 251 | 
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 | 252 | -- some funny zeros [in case of bad signum]
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 | 253 | ddsub370 subtract 1  0  -> 1
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 | 254 | ddsub371 subtract 1 0.  -> 1
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 | 255 | ddsub372 subtract 1  .0 -> 1.0
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 | 256 | ddsub373 subtract 1 0.0 -> 1.0
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 | 257 | ddsub374 subtract  0  1 -> -1
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 | 258 | ddsub375 subtract 0.  1 -> -1
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 | 259 | ddsub376 subtract  .0 1 -> -1.0
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 | 260 | ddsub377 subtract 0.0 1 -> -1.0
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 | 261 | 
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 | 262 | -- leading 0 digit before round
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 | 263 | ddsub910 subtract -103519362 -51897955.3 -> -51621406.7
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 | 264 | ddsub911 subtract 159579.444 89827.5229 -> 69751.9211
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 | 265 | 
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 | 266 | ddsub920 subtract 333.0000000123456 33.00000001234566 -> 299.9999999999999 Inexact Rounded
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 | 267 | ddsub921 subtract 333.0000000123456 33.00000001234565 -> 300.0000000000000 Inexact Rounded
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 | 268 | ddsub922 subtract 133.0000000123456 33.00000001234565 ->  99.99999999999995
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 | 269 | ddsub923 subtract 133.0000000123456 33.00000001234564 ->  99.99999999999996
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 | 270 | ddsub924 subtract 133.0000000123456 33.00000001234540 -> 100.0000000000002 Rounded
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 | 271 | ddsub925 subtract 133.0000000123456 43.00000001234560 ->  90.00000000000000
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 | 272 | ddsub926 subtract 133.0000000123456 43.00000001234561 ->  89.99999999999999
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 | 273 | ddsub927 subtract 133.0000000123456 43.00000001234566 ->  89.99999999999994
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 | 274 | ddsub928 subtract 101.0000000123456 91.00000001234566 ->   9.99999999999994
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 | 275 | ddsub929 subtract 101.0000000123456 99.00000001234566 ->   1.99999999999994
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 | 276 | 
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 | 277 | -- more LHS swaps [were fixed]
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 | 278 | ddsub390 subtract '-56267E-10'   0 ->  '-0.0000056267'
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 | 279 | ddsub391 subtract '-56267E-6'    0 ->  '-0.056267'
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 | 280 | ddsub392 subtract '-56267E-5'    0 ->  '-0.56267'
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 | 281 | ddsub393 subtract '-56267E-4'    0 ->  '-5.6267'
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 | 282 | ddsub394 subtract '-56267E-3'    0 ->  '-56.267'
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 | 283 | ddsub395 subtract '-56267E-2'    0 ->  '-562.67'
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 | 284 | ddsub396 subtract '-56267E-1'    0 ->  '-5626.7'
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 | 285 | ddsub397 subtract '-56267E-0'    0 ->  '-56267'
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 | 286 | ddsub398 subtract '-5E-10'       0 ->  '-5E-10'
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 | 287 | ddsub399 subtract '-5E-7'        0 ->  '-5E-7'
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 | 288 | ddsub400 subtract '-5E-6'        0 ->  '-0.000005'
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 | 289 | ddsub401 subtract '-5E-5'        0 ->  '-0.00005'
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 | 290 | ddsub402 subtract '-5E-4'        0 ->  '-0.0005'
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 | 291 | ddsub403 subtract '-5E-1'        0 ->  '-0.5'
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 | 292 | ddsub404 subtract '-5E0'         0 ->  '-5'
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 | 293 | ddsub405 subtract '-5E1'         0 ->  '-50'
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 | 294 | ddsub406 subtract '-5E5'         0 ->  '-500000'
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 | 295 | ddsub407 subtract '-5E15'        0 ->  '-5000000000000000'
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 | 296 | ddsub408 subtract '-5E16'        0 ->  '-5.000000000000000E+16'  Rounded
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 | 297 | ddsub409 subtract '-5E17'        0 ->  '-5.000000000000000E+17'  Rounded
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 | 298 | ddsub410 subtract '-5E18'        0 ->  '-5.000000000000000E+18'  Rounded
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 | 299 | ddsub411 subtract '-5E100'       0 ->  '-5.000000000000000E+100' Rounded
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 | 300 | 
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 | 301 | -- more RHS swaps [were fixed]
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 | 302 | ddsub420 subtract 0  '-56267E-10' ->  '0.0000056267'
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 | 303 | ddsub421 subtract 0  '-56267E-6'  ->  '0.056267'
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 | 304 | ddsub422 subtract 0  '-56267E-5'  ->  '0.56267'
 | 
 | 305 | ddsub423 subtract 0  '-56267E-4'  ->  '5.6267'
 | 
 | 306 | ddsub424 subtract 0  '-56267E-3'  ->  '56.267'
 | 
 | 307 | ddsub425 subtract 0  '-56267E-2'  ->  '562.67'
 | 
 | 308 | ddsub426 subtract 0  '-56267E-1'  ->  '5626.7'
 | 
 | 309 | ddsub427 subtract 0  '-56267E-0'  ->  '56267'
 | 
 | 310 | ddsub428 subtract 0  '-5E-10'     ->  '5E-10'
 | 
 | 311 | ddsub429 subtract 0  '-5E-7'      ->  '5E-7'
 | 
 | 312 | ddsub430 subtract 0  '-5E-6'      ->  '0.000005'
 | 
 | 313 | ddsub431 subtract 0  '-5E-5'      ->  '0.00005'
 | 
 | 314 | ddsub432 subtract 0  '-5E-4'      ->  '0.0005'
 | 
 | 315 | ddsub433 subtract 0  '-5E-1'      ->  '0.5'
 | 
 | 316 | ddsub434 subtract 0  '-5E0'       ->  '5'
 | 
 | 317 | ddsub435 subtract 0  '-5E1'       ->  '50'
 | 
 | 318 | ddsub436 subtract 0  '-5E5'       ->  '500000'
 | 
 | 319 | ddsub437 subtract 0  '-5E15'      ->  '5000000000000000'
 | 
 | 320 | ddsub438 subtract 0  '-5E16'      ->  '5.000000000000000E+16'   Rounded
 | 
 | 321 | ddsub439 subtract 0  '-5E17'      ->  '5.000000000000000E+17'   Rounded
 | 
 | 322 | ddsub440 subtract 0  '-5E18'      ->  '5.000000000000000E+18'   Rounded
 | 
 | 323 | ddsub441 subtract 0  '-5E100'     ->  '5.000000000000000E+100'  Rounded
 | 
 | 324 | 
 | 
 | 325 | 
 | 
 | 326 | -- try borderline precision, with carries, etc.
 | 
 | 327 | ddsub461 subtract '1E+16' '1'        -> '9999999999999999'
 | 
 | 328 | ddsub462 subtract '1E+12' '-1.111'   -> '1000000000001.111'
 | 
 | 329 | ddsub463 subtract '1.111'  '-1E+12'  -> '1000000000001.111'
 | 
 | 330 | ddsub464 subtract '-1'    '-1E+16'   -> '9999999999999999'
 | 
 | 331 | ddsub465 subtract '7E+15' '1'        -> '6999999999999999'
 | 
 | 332 | ddsub466 subtract '7E+12' '-1.111'   -> '7000000000001.111'
 | 
 | 333 | ddsub467 subtract '1.111'  '-7E+12'  -> '7000000000001.111'
 | 
 | 334 | ddsub468 subtract '-1'    '-7E+15'   -> '6999999999999999'
 | 
 | 335 | 
 | 
 | 336 | --                  1234567890123456       1234567890123456      1 23456789012345
 | 
 | 337 | ddsub470 subtract '0.4444444444444444'  '-0.5555555555555563' -> '1.000000000000001' Inexact Rounded
 | 
 | 338 | ddsub471 subtract '0.4444444444444444'  '-0.5555555555555562' -> '1.000000000000001' Inexact Rounded
 | 
 | 339 | ddsub472 subtract '0.4444444444444444'  '-0.5555555555555561' -> '1.000000000000000' Inexact Rounded
 | 
 | 340 | ddsub473 subtract '0.4444444444444444'  '-0.5555555555555560' -> '1.000000000000000' Inexact Rounded
 | 
 | 341 | ddsub474 subtract '0.4444444444444444'  '-0.5555555555555559' -> '1.000000000000000' Inexact Rounded
 | 
 | 342 | ddsub475 subtract '0.4444444444444444'  '-0.5555555555555558' -> '1.000000000000000' Inexact Rounded
 | 
 | 343 | ddsub476 subtract '0.4444444444444444'  '-0.5555555555555557' -> '1.000000000000000' Inexact Rounded
 | 
 | 344 | ddsub477 subtract '0.4444444444444444'  '-0.5555555555555556' -> '1.000000000000000' Rounded
 | 
 | 345 | ddsub478 subtract '0.4444444444444444'  '-0.5555555555555555' -> '0.9999999999999999'
 | 
 | 346 | ddsub479 subtract '0.4444444444444444'  '-0.5555555555555554' -> '0.9999999999999998'
 | 
 | 347 | ddsub480 subtract '0.4444444444444444'  '-0.5555555555555553' -> '0.9999999999999997'
 | 
 | 348 | ddsub481 subtract '0.4444444444444444'  '-0.5555555555555552' -> '0.9999999999999996'
 | 
 | 349 | ddsub482 subtract '0.4444444444444444'  '-0.5555555555555551' -> '0.9999999999999995'
 | 
 | 350 | ddsub483 subtract '0.4444444444444444'  '-0.5555555555555550' -> '0.9999999999999994'
 | 
 | 351 | 
 | 
 | 352 | -- and some more, including residue effects and different roundings
 | 
 | 353 | rounding: half_up
 | 
 | 354 | ddsub500 subtract '1231234567456789' 0             -> '1231234567456789'
 | 
 | 355 | ddsub501 subtract '1231234567456789' 0.000000001   -> '1231234567456789' Inexact Rounded
 | 
 | 356 | ddsub502 subtract '1231234567456789' 0.000001      -> '1231234567456789' Inexact Rounded
 | 
 | 357 | ddsub503 subtract '1231234567456789' 0.1           -> '1231234567456789' Inexact Rounded
 | 
 | 358 | ddsub504 subtract '1231234567456789' 0.4           -> '1231234567456789' Inexact Rounded
 | 
 | 359 | ddsub505 subtract '1231234567456789' 0.49          -> '1231234567456789' Inexact Rounded
 | 
 | 360 | ddsub506 subtract '1231234567456789' 0.499999      -> '1231234567456789' Inexact Rounded
 | 
 | 361 | ddsub507 subtract '1231234567456789' 0.499999999   -> '1231234567456789' Inexact Rounded
 | 
 | 362 | ddsub508 subtract '1231234567456789' 0.5           -> '1231234567456789' Inexact Rounded
 | 
 | 363 | ddsub509 subtract '1231234567456789' 0.500000001   -> '1231234567456788' Inexact Rounded
 | 
 | 364 | ddsub510 subtract '1231234567456789' 0.500001      -> '1231234567456788' Inexact Rounded
 | 
 | 365 | ddsub511 subtract '1231234567456789' 0.51          -> '1231234567456788' Inexact Rounded
 | 
 | 366 | ddsub512 subtract '1231234567456789' 0.6           -> '1231234567456788' Inexact Rounded
 | 
 | 367 | ddsub513 subtract '1231234567456789' 0.9           -> '1231234567456788' Inexact Rounded
 | 
 | 368 | ddsub514 subtract '1231234567456789' 0.99999       -> '1231234567456788' Inexact Rounded
 | 
 | 369 | ddsub515 subtract '1231234567456789' 0.999999999   -> '1231234567456788' Inexact Rounded
 | 
 | 370 | ddsub516 subtract '1231234567456789' 1             -> '1231234567456788'
 | 
 | 371 | ddsub517 subtract '1231234567456789' 1.000000001   -> '1231234567456788' Inexact Rounded
 | 
 | 372 | ddsub518 subtract '1231234567456789' 1.00001       -> '1231234567456788' Inexact Rounded
 | 
 | 373 | ddsub519 subtract '1231234567456789' 1.1           -> '1231234567456788' Inexact Rounded
 | 
 | 374 | 
 | 
 | 375 | rounding: half_even
 | 
 | 376 | ddsub520 subtract '1231234567456789' 0             -> '1231234567456789'
 | 
 | 377 | ddsub521 subtract '1231234567456789' 0.000000001   -> '1231234567456789' Inexact Rounded
 | 
 | 378 | ddsub522 subtract '1231234567456789' 0.000001      -> '1231234567456789' Inexact Rounded
 | 
 | 379 | ddsub523 subtract '1231234567456789' 0.1           -> '1231234567456789' Inexact Rounded
 | 
 | 380 | ddsub524 subtract '1231234567456789' 0.4           -> '1231234567456789' Inexact Rounded
 | 
 | 381 | ddsub525 subtract '1231234567456789' 0.49          -> '1231234567456789' Inexact Rounded
 | 
 | 382 | ddsub526 subtract '1231234567456789' 0.499999      -> '1231234567456789' Inexact Rounded
 | 
 | 383 | ddsub527 subtract '1231234567456789' 0.499999999   -> '1231234567456789' Inexact Rounded
 | 
 | 384 | ddsub528 subtract '1231234567456789' 0.5           -> '1231234567456788' Inexact Rounded
 | 
 | 385 | ddsub529 subtract '1231234567456789' 0.500000001   -> '1231234567456788' Inexact Rounded
 | 
 | 386 | ddsub530 subtract '1231234567456789' 0.500001      -> '1231234567456788' Inexact Rounded
 | 
 | 387 | ddsub531 subtract '1231234567456789' 0.51          -> '1231234567456788' Inexact Rounded
 | 
 | 388 | ddsub532 subtract '1231234567456789' 0.6           -> '1231234567456788' Inexact Rounded
 | 
 | 389 | ddsub533 subtract '1231234567456789' 0.9           -> '1231234567456788' Inexact Rounded
 | 
 | 390 | ddsub534 subtract '1231234567456789' 0.99999       -> '1231234567456788' Inexact Rounded
 | 
 | 391 | ddsub535 subtract '1231234567456789' 0.999999999   -> '1231234567456788' Inexact Rounded
 | 
 | 392 | ddsub536 subtract '1231234567456789' 1             -> '1231234567456788'
 | 
 | 393 | ddsub537 subtract '1231234567456789' 1.00000001    -> '1231234567456788' Inexact Rounded
 | 
 | 394 | ddsub538 subtract '1231234567456789' 1.00001       -> '1231234567456788' Inexact Rounded
 | 
 | 395 | ddsub539 subtract '1231234567456789' 1.1           -> '1231234567456788' Inexact Rounded
 | 
 | 396 | -- critical few with even bottom digit...
 | 
 | 397 | ddsub540 subtract '1231234567456788' 0.499999999   -> '1231234567456788' Inexact Rounded
 | 
 | 398 | ddsub541 subtract '1231234567456788' 0.5           -> '1231234567456788' Inexact Rounded
 | 
 | 399 | ddsub542 subtract '1231234567456788' 0.500000001   -> '1231234567456787' Inexact Rounded
 | 
 | 400 | 
 | 
 | 401 | rounding: down
 | 
 | 402 | ddsub550 subtract '1231234567456789' 0             -> '1231234567456789'
 | 
 | 403 | ddsub551 subtract '1231234567456789' 0.000000001   -> '1231234567456788' Inexact Rounded
 | 
 | 404 | ddsub552 subtract '1231234567456789' 0.000001      -> '1231234567456788' Inexact Rounded
 | 
 | 405 | ddsub553 subtract '1231234567456789' 0.1           -> '1231234567456788' Inexact Rounded
 | 
 | 406 | ddsub554 subtract '1231234567456789' 0.4           -> '1231234567456788' Inexact Rounded
 | 
 | 407 | ddsub555 subtract '1231234567456789' 0.49          -> '1231234567456788' Inexact Rounded
 | 
 | 408 | ddsub556 subtract '1231234567456789' 0.499999      -> '1231234567456788' Inexact Rounded
 | 
 | 409 | ddsub557 subtract '1231234567456789' 0.499999999   -> '1231234567456788' Inexact Rounded
 | 
 | 410 | ddsub558 subtract '1231234567456789' 0.5           -> '1231234567456788' Inexact Rounded
 | 
 | 411 | ddsub559 subtract '1231234567456789' 0.500000001   -> '1231234567456788' Inexact Rounded
 | 
 | 412 | ddsub560 subtract '1231234567456789' 0.500001      -> '1231234567456788' Inexact Rounded
 | 
 | 413 | ddsub561 subtract '1231234567456789' 0.51          -> '1231234567456788' Inexact Rounded
 | 
 | 414 | ddsub562 subtract '1231234567456789' 0.6           -> '1231234567456788' Inexact Rounded
 | 
 | 415 | ddsub563 subtract '1231234567456789' 0.9           -> '1231234567456788' Inexact Rounded
 | 
 | 416 | ddsub564 subtract '1231234567456789' 0.99999       -> '1231234567456788' Inexact Rounded
 | 
 | 417 | ddsub565 subtract '1231234567456789' 0.999999999   -> '1231234567456788' Inexact Rounded
 | 
 | 418 | ddsub566 subtract '1231234567456789' 1             -> '1231234567456788'
 | 
 | 419 | ddsub567 subtract '1231234567456789' 1.00000001    -> '1231234567456787' Inexact Rounded
 | 
 | 420 | ddsub568 subtract '1231234567456789' 1.00001       -> '1231234567456787' Inexact Rounded
 | 
 | 421 | ddsub569 subtract '1231234567456789' 1.1           -> '1231234567456787' Inexact Rounded
 | 
 | 422 | 
 | 
 | 423 | -- symmetry...
 | 
 | 424 | rounding: half_up
 | 
 | 425 | ddsub600 subtract 0             '1231234567456789' -> '-1231234567456789'
 | 
 | 426 | ddsub601 subtract 0.000000001   '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 427 | ddsub602 subtract 0.000001      '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 428 | ddsub603 subtract 0.1           '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 429 | ddsub604 subtract 0.4           '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 430 | ddsub605 subtract 0.49          '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 431 | ddsub606 subtract 0.499999      '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 432 | ddsub607 subtract 0.499999999   '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 433 | ddsub608 subtract 0.5           '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 434 | ddsub609 subtract 0.500000001   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 435 | ddsub610 subtract 0.500001      '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 436 | ddsub611 subtract 0.51          '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 437 | ddsub612 subtract 0.6           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 438 | ddsub613 subtract 0.9           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 439 | ddsub614 subtract 0.99999       '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 440 | ddsub615 subtract 0.999999999   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 441 | ddsub616 subtract 1             '1231234567456789' -> '-1231234567456788'
 | 
 | 442 | ddsub617 subtract 1.000000001   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 443 | ddsub618 subtract 1.00001       '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 444 | ddsub619 subtract 1.1           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 445 | 
 | 
 | 446 | rounding: half_even
 | 
 | 447 | ddsub620 subtract 0             '1231234567456789' -> '-1231234567456789'
 | 
 | 448 | ddsub621 subtract 0.000000001   '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 449 | ddsub622 subtract 0.000001      '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 450 | ddsub623 subtract 0.1           '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 451 | ddsub624 subtract 0.4           '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 452 | ddsub625 subtract 0.49          '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 453 | ddsub626 subtract 0.499999      '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 454 | ddsub627 subtract 0.499999999   '1231234567456789' -> '-1231234567456789' Inexact Rounded
 | 
 | 455 | ddsub628 subtract 0.5           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 456 | ddsub629 subtract 0.500000001   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 457 | ddsub630 subtract 0.500001      '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 458 | ddsub631 subtract 0.51          '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 459 | ddsub632 subtract 0.6           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 460 | ddsub633 subtract 0.9           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 461 | ddsub634 subtract 0.99999       '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 462 | ddsub635 subtract 0.999999999   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 463 | ddsub636 subtract 1             '1231234567456789' -> '-1231234567456788'
 | 
 | 464 | ddsub637 subtract 1.00000001    '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 465 | ddsub638 subtract 1.00001       '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 466 | ddsub639 subtract 1.1           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 467 | -- critical few with even bottom digit...
 | 
 | 468 | ddsub640 subtract 0.499999999   '1231234567456788' -> '-1231234567456788' Inexact Rounded
 | 
 | 469 | ddsub641 subtract 0.5           '1231234567456788' -> '-1231234567456788' Inexact Rounded
 | 
 | 470 | ddsub642 subtract 0.500000001   '1231234567456788' -> '-1231234567456787' Inexact Rounded
 | 
 | 471 | 
 | 
 | 472 | rounding: down
 | 
 | 473 | ddsub650 subtract 0             '1231234567456789' -> '-1231234567456789'
 | 
 | 474 | ddsub651 subtract 0.000000001   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 475 | ddsub652 subtract 0.000001      '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 476 | ddsub653 subtract 0.1           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 477 | ddsub654 subtract 0.4           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 478 | ddsub655 subtract 0.49          '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 479 | ddsub656 subtract 0.499999      '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 480 | ddsub657 subtract 0.499999999   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 481 | ddsub658 subtract 0.5           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 482 | ddsub659 subtract 0.500000001   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 483 | ddsub660 subtract 0.500001      '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 484 | ddsub661 subtract 0.51          '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 485 | ddsub662 subtract 0.6           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 486 | ddsub663 subtract 0.9           '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 487 | ddsub664 subtract 0.99999       '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 488 | ddsub665 subtract 0.999999999   '1231234567456789' -> '-1231234567456788' Inexact Rounded
 | 
 | 489 | ddsub666 subtract 1             '1231234567456789' -> '-1231234567456788'
 | 
 | 490 | ddsub667 subtract 1.00000001    '1231234567456789' -> '-1231234567456787' Inexact Rounded
 | 
 | 491 | ddsub668 subtract 1.00001       '1231234567456789' -> '-1231234567456787' Inexact Rounded
 | 
 | 492 | ddsub669 subtract 1.1           '1231234567456789' -> '-1231234567456787' Inexact Rounded
 | 
 | 493 | 
 | 
 | 494 | 
 | 
 | 495 | -- lots of leading zeros in intermediate result, and showing effects of
 | 
 | 496 | -- input rounding would have affected the following
 | 
 | 497 | rounding: half_up
 | 
 | 498 | ddsub670 subtract '1234567456789' '1234567456788.1' -> 0.9
 | 
 | 499 | ddsub671 subtract '1234567456789' '1234567456788.9' -> 0.1
 | 
 | 500 | ddsub672 subtract '1234567456789' '1234567456789.1' -> -0.1
 | 
 | 501 | ddsub673 subtract '1234567456789' '1234567456789.5' -> -0.5
 | 
 | 502 | ddsub674 subtract '1234567456789' '1234567456789.9' -> -0.9
 | 
 | 503 | 
 | 
 | 504 | rounding: half_even
 | 
 | 505 | ddsub680 subtract '1234567456789' '1234567456788.1' -> 0.9
 | 
 | 506 | ddsub681 subtract '1234567456789' '1234567456788.9' -> 0.1
 | 
 | 507 | ddsub682 subtract '1234567456789' '1234567456789.1' -> -0.1
 | 
 | 508 | ddsub683 subtract '1234567456789' '1234567456789.5' -> -0.5
 | 
 | 509 | ddsub684 subtract '1234567456789' '1234567456789.9' -> -0.9
 | 
 | 510 | 
 | 
 | 511 | ddsub685 subtract '1234567456788' '1234567456787.1' -> 0.9
 | 
 | 512 | ddsub686 subtract '1234567456788' '1234567456787.9' -> 0.1
 | 
 | 513 | ddsub687 subtract '1234567456788' '1234567456788.1' -> -0.1
 | 
 | 514 | ddsub688 subtract '1234567456788' '1234567456788.5' -> -0.5
 | 
 | 515 | ddsub689 subtract '1234567456788' '1234567456788.9' -> -0.9
 | 
 | 516 | 
 | 
 | 517 | rounding: down
 | 
 | 518 | ddsub690 subtract '1234567456789' '1234567456788.1' -> 0.9
 | 
 | 519 | ddsub691 subtract '1234567456789' '1234567456788.9' -> 0.1
 | 
 | 520 | ddsub692 subtract '1234567456789' '1234567456789.1' -> -0.1
 | 
 | 521 | ddsub693 subtract '1234567456789' '1234567456789.5' -> -0.5
 | 
 | 522 | ddsub694 subtract '1234567456789' '1234567456789.9' -> -0.9
 | 
 | 523 | 
 | 
 | 524 | -- Specials
 | 
 | 525 | ddsub780 subtract -Inf   Inf   -> -Infinity
 | 
 | 526 | ddsub781 subtract -Inf   1000  -> -Infinity
 | 
 | 527 | ddsub782 subtract -Inf   1     -> -Infinity
 | 
 | 528 | ddsub783 subtract -Inf  -0     -> -Infinity
 | 
 | 529 | ddsub784 subtract -Inf  -1     -> -Infinity
 | 
 | 530 | ddsub785 subtract -Inf  -1000  -> -Infinity
 | 
 | 531 | ddsub787 subtract -1000  Inf   -> -Infinity
 | 
 | 532 | ddsub788 subtract -Inf   Inf   -> -Infinity
 | 
 | 533 | ddsub789 subtract -1     Inf   -> -Infinity
 | 
 | 534 | ddsub790 subtract  0     Inf   -> -Infinity
 | 
 | 535 | ddsub791 subtract  1     Inf   -> -Infinity
 | 
 | 536 | ddsub792 subtract  1000  Inf   -> -Infinity
 | 
 | 537 | 
 | 
 | 538 | ddsub800 subtract  Inf   Inf   ->  NaN  Invalid_operation
 | 
 | 539 | ddsub801 subtract  Inf   1000  ->  Infinity
 | 
 | 540 | ddsub802 subtract  Inf   1     ->  Infinity
 | 
 | 541 | ddsub803 subtract  Inf   0     ->  Infinity
 | 
 | 542 | ddsub804 subtract  Inf  -0     ->  Infinity
 | 
 | 543 | ddsub805 subtract  Inf  -1     ->  Infinity
 | 
 | 544 | ddsub806 subtract  Inf  -1000  ->  Infinity
 | 
 | 545 | ddsub807 subtract  Inf  -Inf   ->  Infinity
 | 
 | 546 | ddsub808 subtract -1000 -Inf   ->  Infinity
 | 
 | 547 | ddsub809 subtract -Inf  -Inf   ->  NaN  Invalid_operation
 | 
 | 548 | ddsub810 subtract -1    -Inf   ->  Infinity
 | 
 | 549 | ddsub811 subtract -0    -Inf   ->  Infinity
 | 
 | 550 | ddsub812 subtract  0    -Inf   ->  Infinity
 | 
 | 551 | ddsub813 subtract  1    -Inf   ->  Infinity
 | 
 | 552 | ddsub814 subtract  1000 -Inf   ->  Infinity
 | 
 | 553 | ddsub815 subtract  Inf  -Inf   ->  Infinity
 | 
 | 554 | 
 | 
 | 555 | ddsub821 subtract  NaN   Inf   ->  NaN
 | 
 | 556 | ddsub822 subtract -NaN   1000  -> -NaN
 | 
 | 557 | ddsub823 subtract  NaN   1     ->  NaN
 | 
 | 558 | ddsub824 subtract  NaN   0     ->  NaN
 | 
 | 559 | ddsub825 subtract  NaN  -0     ->  NaN
 | 
 | 560 | ddsub826 subtract  NaN  -1     ->  NaN
 | 
 | 561 | ddsub827 subtract  NaN  -1000  ->  NaN
 | 
 | 562 | ddsub828 subtract  NaN  -Inf   ->  NaN
 | 
 | 563 | ddsub829 subtract -NaN   NaN   -> -NaN
 | 
 | 564 | ddsub830 subtract -Inf   NaN   ->  NaN
 | 
 | 565 | ddsub831 subtract -1000  NaN   ->  NaN
 | 
 | 566 | ddsub832 subtract -1     NaN   ->  NaN
 | 
 | 567 | ddsub833 subtract -0     NaN   ->  NaN
 | 
 | 568 | ddsub834 subtract  0     NaN   ->  NaN
 | 
 | 569 | ddsub835 subtract  1     NaN   ->  NaN
 | 
 | 570 | ddsub836 subtract  1000 -NaN   -> -NaN
 | 
 | 571 | ddsub837 subtract  Inf   NaN   ->  NaN
 | 
 | 572 | 
 | 
 | 573 | ddsub841 subtract  sNaN  Inf   ->  NaN  Invalid_operation
 | 
 | 574 | ddsub842 subtract -sNaN  1000  -> -NaN  Invalid_operation
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 | 575 | ddsub843 subtract  sNaN  1     ->  NaN  Invalid_operation
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 | 576 | ddsub844 subtract  sNaN  0     ->  NaN  Invalid_operation
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 | 577 | ddsub845 subtract  sNaN -0     ->  NaN  Invalid_operation
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 | 578 | ddsub846 subtract  sNaN -1     ->  NaN  Invalid_operation
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 | 579 | ddsub847 subtract  sNaN -1000  ->  NaN  Invalid_operation
 | 
 | 580 | ddsub848 subtract  sNaN  NaN   ->  NaN  Invalid_operation
 | 
 | 581 | ddsub849 subtract  sNaN sNaN   ->  NaN  Invalid_operation
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 | 582 | ddsub850 subtract  NaN  sNaN   ->  NaN  Invalid_operation
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 | 583 | ddsub851 subtract -Inf -sNaN   -> -NaN  Invalid_operation
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 | 584 | ddsub852 subtract -1000 sNaN   ->  NaN  Invalid_operation
 | 
 | 585 | ddsub853 subtract -1    sNaN   ->  NaN  Invalid_operation
 | 
 | 586 | ddsub854 subtract -0    sNaN   ->  NaN  Invalid_operation
 | 
 | 587 | ddsub855 subtract  0    sNaN   ->  NaN  Invalid_operation
 | 
 | 588 | ddsub856 subtract  1    sNaN   ->  NaN  Invalid_operation
 | 
 | 589 | ddsub857 subtract  1000 sNaN   ->  NaN  Invalid_operation
 | 
 | 590 | ddsub858 subtract  Inf  sNaN   ->  NaN  Invalid_operation
 | 
 | 591 | ddsub859 subtract  NaN  sNaN   ->  NaN  Invalid_operation
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 | 592 | 
 | 
 | 593 | -- propagating NaNs
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 | 594 | ddsub861 subtract  NaN01   -Inf     ->  NaN1
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 | 595 | ddsub862 subtract -NaN02   -1000    -> -NaN2
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 | 596 | ddsub863 subtract  NaN03    1000    ->  NaN3
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 | 597 | ddsub864 subtract  NaN04    Inf     ->  NaN4
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 | 598 | ddsub865 subtract  NaN05    NaN61   ->  NaN5
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 | 599 | ddsub866 subtract -Inf     -NaN71   -> -NaN71
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 | 600 | ddsub867 subtract -1000     NaN81   ->  NaN81
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 | 601 | ddsub868 subtract  1000     NaN91   ->  NaN91
 | 
 | 602 | ddsub869 subtract  Inf      NaN101  ->  NaN101
 | 
 | 603 | ddsub871 subtract  sNaN011  -Inf    ->  NaN11  Invalid_operation
 | 
 | 604 | ddsub872 subtract  sNaN012  -1000   ->  NaN12  Invalid_operation
 | 
 | 605 | ddsub873 subtract -sNaN013   1000   -> -NaN13  Invalid_operation
 | 
 | 606 | ddsub874 subtract  sNaN014   NaN171 ->  NaN14  Invalid_operation
 | 
 | 607 | ddsub875 subtract  sNaN015  sNaN181 ->  NaN15  Invalid_operation
 | 
 | 608 | ddsub876 subtract  NaN016   sNaN191 ->  NaN191 Invalid_operation
 | 
 | 609 | ddsub877 subtract -Inf      sNaN201 ->  NaN201 Invalid_operation
 | 
 | 610 | ddsub878 subtract -1000     sNaN211 ->  NaN211 Invalid_operation
 | 
 | 611 | ddsub879 subtract  1000    -sNaN221 -> -NaN221 Invalid_operation
 | 
 | 612 | ddsub880 subtract  Inf      sNaN231 ->  NaN231 Invalid_operation
 | 
 | 613 | ddsub881 subtract  NaN025   sNaN241 ->  NaN241 Invalid_operation
 | 
 | 614 | 
 | 
 | 615 | -- edge case spills
 | 
 | 616 | ddsub901 subtract  2.E-3  1.002  -> -1.000
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 | 617 | ddsub902 subtract  2.0E-3  1.002  -> -1.0000
 | 
 | 618 | ddsub903 subtract  2.00E-3  1.0020  -> -1.00000
 | 
 | 619 | ddsub904 subtract  2.000E-3  1.00200  -> -1.000000
 | 
 | 620 | ddsub905 subtract  2.0000E-3  1.002000  -> -1.0000000
 | 
 | 621 | ddsub906 subtract  2.00000E-3  1.0020000  -> -1.00000000
 | 
 | 622 | ddsub907 subtract  2.000000E-3  1.00200000  -> -1.000000000
 | 
 | 623 | ddsub908 subtract  2.0000000E-3  1.002000000  -> -1.0000000000
 | 
 | 624 | 
 | 
 | 625 | -- subnormals and overflows covered under Add
 | 
 | 626 | 
 | 
 | 627 | -- Null tests
 | 
 | 628 | ddsub9990 subtract 10  # -> NaN Invalid_operation
 | 
 | 629 | ddsub9991 subtract  # 10 -> NaN Invalid_operation
 |