Demonstrate how to round final result.
diff --git a/Doc/lib/libdecimal.tex b/Doc/lib/libdecimal.tex
index 08c9b9e..66aad93 100644
--- a/Doc/lib/libdecimal.tex
+++ b/Doc/lib/libdecimal.tex
@@ -932,9 +932,9 @@
"""Compute Pi to the current precision.
>>> print pi()
- 3.141592653589793238462643383279502887
+ 3.141592653589793238462643383
"""
- getcontext().prec += 9 # extra digits for intermediate steps
+ getcontext().prec += 2 # extra digits for intermediate steps
three = Decimal(3) # substitute "three=3.0" for regular floats
lastc, t, c, n, na, d, da = 0, three, 3, 1, 0, 0, 24
while c != lastc:
@@ -943,22 +943,22 @@
d, da = d+da, da+32
t = (t * n) / d
c += t
- getcontext().prec -= 9
- return c
+ getcontext().prec -= 2
+ return c + 0
def exp(x):
"""Return e raised to the power of x. Result type matches input type.
>>> print exp(Decimal(1))
- 2.718281828459045235360287471352662498
+ 2.718281828459045235360287471
>>> print exp(Decimal(2))
- 7.389056098930650227230427460575007813
+ 7.389056098930650227230427461
>>> print exp(2.0)
7.38905609893
>>> print exp(2+0j)
(7.38905609893+0j)
"""
- getcontext().prec += 9 # extra digits for intermediate steps
+ getcontext().prec += 2 # extra digits for intermediate steps
i, laste, e, fact, num = 0, 0, 1, 1, 1
while e != laste:
laste = e
@@ -966,20 +966,20 @@
fact *= i
num *= x
e += num / fact
- getcontext().prec -= 9
- return e
+ getcontext().prec -= 2
+ return e + 0
def cos(x):
"""Return the cosine of x as measured in radians.
>>> print cos(Decimal('0.5'))
- 0.8775825618903727161162815826038296521
+ 0.8775825618903727161162815826
>>> print cos(0.5)
0.87758256189
>>> print cos(0.5+0j)
(0.87758256189+0j)
"""
- getcontext().prec += 9 # extra digits for intermediate steps
+ getcontext().prec += 2 # extra digits for intermediate steps
i, laste, e, fact, num, sign = 0, 0, 1, 1, 1, 1
while e != laste:
laste = e
@@ -988,20 +988,20 @@
num *= x * x
sign *= -1
e += num / fact * sign
- getcontext().prec -= 9
- return e
+ getcontext().prec -= 2
+ return e + 0
def sin(x):
"""Return the cosine of x as measured in radians.
>>> print sin(Decimal('0.5'))
- 0.4794255386042030002732879352155713880
+ 0.4794255386042030002732879352
>>> print sin(0.5)
0.479425538604
>>> print sin(0.5+0j)
(0.479425538604+0j)
"""
- getcontext().prec += 9 # extra digits for intermediate steps
+ getcontext().prec += 2 # extra digits for intermediate steps
i, laste, e, fact, num, sign = 1, 0, x, 1, x, 1
while e != laste:
laste = e
@@ -1010,7 +1010,7 @@
num *= x * x
sign *= -1
e += num / fact * sign
- getcontext().prec -= 9
- return e
+ getcontext().prec -= 2
+ return e + 0
\end{verbatim}