| #! /usr/bin/env python |
| |
| """Sorting algorithms visualizer using Tkinter. |
| |
| This module is comprised of three ``components'': |
| |
| - an array visualizer with methods that implement basic sorting |
| operations (compare, swap) as well as methods for ``annotating'' the |
| sorting algorithm (e.g. to show the pivot element); |
| |
| - a number of sorting algorithms (currently quicksort, insertion sort, |
| selection sort and bubble sort, as well as a randomization function), |
| all using the array visualizer for its basic operations and with calls |
| to its annotation methods; |
| |
| - and a ``driver'' class which can be used as a Grail applet or as a |
| stand-alone application. |
| |
| """ |
| |
| |
| from Tkinter import * |
| from Canvas import Line, Rectangle |
| import random |
| |
| |
| XGRID = 10 |
| YGRID = 10 |
| WIDTH = 6 |
| |
| |
| class Array: |
| |
| def __init__(self, master, data=None): |
| self.master = master |
| self.frame = Frame(self.master) |
| self.frame.pack(fill=X) |
| self.label = Label(self.frame) |
| self.label.pack() |
| self.canvas = Canvas(self.frame) |
| self.canvas.pack() |
| self.report = Label(self.frame) |
| self.report.pack() |
| self.left = Line(self.canvas, 0, 0, 0, 0) |
| self.right = Line(self.canvas, 0, 0, 0, 0) |
| self.pivot = Line(self.canvas, 0, 0, 0, 0) |
| self.items = [] |
| self.size = self.maxvalue = 0 |
| if data: |
| self.setdata(data) |
| |
| def setdata(self, data): |
| olditems = self.items |
| self.items = [] |
| for item in olditems: |
| item.delete() |
| self.size = len(data) |
| self.maxvalue = max(data) |
| self.canvas.config(width=(self.size+1)*XGRID, |
| height=(self.maxvalue+1)*YGRID) |
| for i in range(self.size): |
| self.items.append(ArrayItem(self, i, data[i])) |
| self.reset("Sort demo, size %d" % self.size) |
| |
| speed = "normal" |
| |
| def setspeed(self, speed): |
| self.speed = speed |
| |
| def destroy(self): |
| self.frame.destroy() |
| |
| in_mainloop = 0 |
| stop_mainloop = 0 |
| |
| def cancel(self): |
| self.stop_mainloop = 1 |
| if self.in_mainloop: |
| self.master.quit() |
| |
| def step(self): |
| if self.in_mainloop: |
| self.master.quit() |
| |
| Cancelled = "Array.Cancelled" # Exception |
| |
| def wait(self, msecs): |
| if self.speed == "fastest": |
| msecs = 0 |
| elif self.speed == "fast": |
| msecs = msecs/10 |
| elif self.speed == "single-step": |
| msecs = 1000000000 |
| if not self.stop_mainloop: |
| self.master.update() |
| id = self.master.after(msecs, self.master.quit) |
| self.in_mainloop = 1 |
| self.master.mainloop() |
| self.master.after_cancel(id) |
| self.in_mainloop = 0 |
| if self.stop_mainloop: |
| self.stop_mainloop = 0 |
| self.message("Cancelled") |
| raise Array.Cancelled |
| |
| def getsize(self): |
| return self.size |
| |
| def show_partition(self, first, last): |
| for i in range(self.size): |
| item = self.items[i] |
| if first <= i < last: |
| item.item.config(fill='red') |
| else: |
| item.item.config(fill='orange') |
| self.hide_left_right_pivot() |
| |
| def hide_partition(self): |
| for i in range(self.size): |
| item = self.items[i] |
| item.item.config(fill='red') |
| self.hide_left_right_pivot() |
| |
| def show_left(self, left): |
| if not 0 <= left < self.size: |
| self.hide_left() |
| return |
| x1, y1, x2, y2 = self.items[left].position() |
| ## top, bot = HIRO |
| self.left.coords([(x1-2, 0), (x1-2, 9999)]) |
| self.master.update() |
| |
| def show_right(self, right): |
| if not 0 <= right < self.size: |
| self.hide_right() |
| return |
| x1, y1, x2, y2 = self.items[right].position() |
| self.right.coords(((x2+2, 0), (x2+2, 9999))) |
| self.master.update() |
| |
| def hide_left_right_pivot(self): |
| self.hide_left() |
| self.hide_right() |
| self.hide_pivot() |
| |
| def hide_left(self): |
| self.left.coords(((0, 0), (0, 0))) |
| |
| def hide_right(self): |
| self.right.coords(((0, 0), (0, 0))) |
| |
| def show_pivot(self, pivot): |
| x1, y1, x2, y2 = self.items[pivot].position() |
| self.pivot.coords(((0, y1-2), (9999, y1-2))) |
| |
| def hide_pivot(self): |
| self.pivot.coords(((0, 0), (0, 0))) |
| |
| def swap(self, i, j): |
| if i == j: return |
| self.countswap() |
| item = self.items[i] |
| other = self.items[j] |
| self.items[i], self.items[j] = other, item |
| item.swapwith(other) |
| |
| def compare(self, i, j): |
| self.countcompare() |
| item = self.items[i] |
| other = self.items[j] |
| return item.compareto(other) |
| |
| def reset(self, msg): |
| self.ncompares = 0 |
| self.nswaps = 0 |
| self.message(msg) |
| self.updatereport() |
| self.hide_partition() |
| |
| def message(self, msg): |
| self.label.config(text=msg) |
| |
| def countswap(self): |
| self.nswaps = self.nswaps + 1 |
| self.updatereport() |
| |
| def countcompare(self): |
| self.ncompares = self.ncompares + 1 |
| self.updatereport() |
| |
| def updatereport(self): |
| text = "%d cmps, %d swaps" % (self.ncompares, self.nswaps) |
| self.report.config(text=text) |
| |
| |
| class ArrayItem: |
| |
| def __init__(self, array, index, value): |
| self.array = array |
| self.index = index |
| self.value = value |
| x1, y1, x2, y2 = self.position() |
| self.item = Rectangle(array.canvas, x1, y1, x2, y2, |
| fill='red', outline='black', width=1) |
| self.item.bind('<Button-1>', self.mouse_down) |
| self.item.bind('<Button1-Motion>', self.mouse_move) |
| self.item.bind('<ButtonRelease-1>', self.mouse_up) |
| |
| def delete(self): |
| item = self.item |
| self.array = None |
| self.item = None |
| item.delete() |
| |
| def mouse_down(self, event): |
| self.lastx = event.x |
| self.lasty = event.y |
| self.origx = event.x |
| self.origy = event.y |
| self.item.tkraise() |
| |
| def mouse_move(self, event): |
| self.item.move(event.x - self.lastx, event.y - self.lasty) |
| self.lastx = event.x |
| self.lasty = event.y |
| |
| def mouse_up(self, event): |
| i = self.nearestindex(event.x) |
| if i >= self.array.getsize(): |
| i = self.array.getsize() - 1 |
| if i < 0: |
| i = 0 |
| other = self.array.items[i] |
| here = self.index |
| self.array.items[here], self.array.items[i] = other, self |
| self.index = i |
| x1, y1, x2, y2 = self.position() |
| self.item.coords(((x1, y1), (x2, y2))) |
| other.setindex(here) |
| |
| def setindex(self, index): |
| nsteps = steps(self.index, index) |
| if not nsteps: return |
| if self.array.speed == "fastest": |
| nsteps = 0 |
| oldpts = self.position() |
| self.index = index |
| newpts = self.position() |
| trajectory = interpolate(oldpts, newpts, nsteps) |
| self.item.tkraise() |
| for pts in trajectory: |
| self.item.coords((pts[:2], pts[2:])) |
| self.array.wait(50) |
| |
| def swapwith(self, other): |
| nsteps = steps(self.index, other.index) |
| if not nsteps: return |
| if self.array.speed == "fastest": |
| nsteps = 0 |
| myoldpts = self.position() |
| otheroldpts = other.position() |
| self.index, other.index = other.index, self.index |
| mynewpts = self.position() |
| othernewpts = other.position() |
| myfill = self.item['fill'] |
| otherfill = other.item['fill'] |
| self.item.config(fill='green') |
| other.item.config(fill='yellow') |
| self.array.master.update() |
| if self.array.speed == "single-step": |
| self.item.coords((mynewpts[:2], mynewpts[2:])) |
| other.item.coords((othernewpts[:2], othernewpts[2:])) |
| self.array.master.update() |
| self.item.config(fill=myfill) |
| other.item.config(fill=otherfill) |
| self.array.wait(0) |
| return |
| mytrajectory = interpolate(myoldpts, mynewpts, nsteps) |
| othertrajectory = interpolate(otheroldpts, othernewpts, nsteps) |
| if self.value > other.value: |
| self.item.tkraise() |
| other.item.tkraise() |
| else: |
| other.item.tkraise() |
| self.item.tkraise() |
| try: |
| for i in range(len(mytrajectory)): |
| mypts = mytrajectory[i] |
| otherpts = othertrajectory[i] |
| self.item.coords((mypts[:2], mypts[2:])) |
| other.item.coords((otherpts[:2], otherpts[2:])) |
| self.array.wait(50) |
| finally: |
| mypts = mytrajectory[-1] |
| otherpts = othertrajectory[-1] |
| self.item.coords((mypts[:2], mypts[2:])) |
| other.item.coords((otherpts[:2], otherpts[2:])) |
| self.item.config(fill=myfill) |
| other.item.config(fill=otherfill) |
| |
| def compareto(self, other): |
| myfill = self.item['fill'] |
| otherfill = other.item['fill'] |
| outcome = cmp(self.value, other.value) |
| if outcome < 0: |
| myflash = 'white' |
| otherflash = 'black' |
| elif outcome > 0: |
| myflash = 'black' |
| otherflash = 'white' |
| else: |
| myflash = otherflash = 'grey' |
| try: |
| self.item.config(fill=myflash) |
| other.item.config(fill=otherflash) |
| self.array.wait(500) |
| finally: |
| self.item.config(fill=myfill) |
| other.item.config(fill=otherfill) |
| return outcome |
| |
| def position(self): |
| x1 = (self.index+1)*XGRID - WIDTH/2 |
| x2 = x1+WIDTH |
| y2 = (self.array.maxvalue+1)*YGRID |
| y1 = y2 - (self.value)*YGRID |
| return x1, y1, x2, y2 |
| |
| def nearestindex(self, x): |
| return int(round(float(x)/XGRID)) - 1 |
| |
| |
| # Subroutines that don't need an object |
| |
| def steps(here, there): |
| nsteps = abs(here - there) |
| if nsteps <= 3: |
| nsteps = nsteps * 3 |
| elif nsteps <= 5: |
| nsteps = nsteps * 2 |
| elif nsteps > 10: |
| nsteps = 10 |
| return nsteps |
| |
| def interpolate(oldpts, newpts, n): |
| if len(oldpts) != len(newpts): |
| raise ValueError, "can't interpolate arrays of different length" |
| pts = [0]*len(oldpts) |
| res = [tuple(oldpts)] |
| for i in range(1, n): |
| for k in range(len(pts)): |
| pts[k] = oldpts[k] + (newpts[k] - oldpts[k])*i/n |
| res.append(tuple(pts)) |
| res.append(tuple(newpts)) |
| return res |
| |
| |
| # Various (un)sorting algorithms |
| |
| def uniform(array): |
| size = array.getsize() |
| array.setdata([(size+1)/2] * size) |
| array.reset("Uniform data, size %d" % size) |
| |
| def distinct(array): |
| size = array.getsize() |
| array.setdata(range(1, size+1)) |
| array.reset("Distinct data, size %d" % size) |
| |
| def randomize(array): |
| array.reset("Randomizing") |
| n = array.getsize() |
| for i in range(n): |
| j = random.randint(0, n-1) |
| array.swap(i, j) |
| array.message("Randomized") |
| |
| def insertionsort(array): |
| size = array.getsize() |
| array.reset("Insertion sort") |
| for i in range(1, size): |
| j = i-1 |
| while j >= 0: |
| if array.compare(j, j+1) <= 0: |
| break |
| array.swap(j, j+1) |
| j = j-1 |
| array.message("Sorted") |
| |
| def selectionsort(array): |
| size = array.getsize() |
| array.reset("Selection sort") |
| try: |
| for i in range(size): |
| array.show_partition(i, size) |
| for j in range(i+1, size): |
| if array.compare(i, j) > 0: |
| array.swap(i, j) |
| array.message("Sorted") |
| finally: |
| array.hide_partition() |
| |
| def bubblesort(array): |
| size = array.getsize() |
| array.reset("Bubble sort") |
| for i in range(size): |
| for j in range(1, size): |
| if array.compare(j-1, j) > 0: |
| array.swap(j-1, j) |
| array.message("Sorted") |
| |
| def quicksort(array): |
| size = array.getsize() |
| array.reset("Quicksort") |
| try: |
| stack = [(0, size)] |
| while stack: |
| first, last = stack[-1] |
| del stack[-1] |
| array.show_partition(first, last) |
| if last-first < 5: |
| array.message("Insertion sort") |
| for i in range(first+1, last): |
| j = i-1 |
| while j >= first: |
| if array.compare(j, j+1) <= 0: |
| break |
| array.swap(j, j+1) |
| j = j-1 |
| continue |
| array.message("Choosing pivot") |
| j, i, k = first, (first+last)/2, last-1 |
| if array.compare(k, i) < 0: |
| array.swap(k, i) |
| if array.compare(k, j) < 0: |
| array.swap(k, j) |
| if array.compare(j, i) < 0: |
| array.swap(j, i) |
| pivot = j |
| array.show_pivot(pivot) |
| array.message("Pivot at left of partition") |
| array.wait(1000) |
| left = first |
| right = last |
| while 1: |
| array.message("Sweep right pointer") |
| right = right-1 |
| array.show_right(right) |
| while right > first and array.compare(right, pivot) >= 0: |
| right = right-1 |
| array.show_right(right) |
| array.message("Sweep left pointer") |
| left = left+1 |
| array.show_left(left) |
| while left < last and array.compare(left, pivot) <= 0: |
| left = left+1 |
| array.show_left(left) |
| if left > right: |
| array.message("End of partition") |
| break |
| array.message("Swap items") |
| array.swap(left, right) |
| array.message("Swap pivot back") |
| array.swap(pivot, right) |
| n1 = right-first |
| n2 = last-left |
| if n1 > 1: stack.append((first, right)) |
| if n2 > 1: stack.append((left, last)) |
| array.message("Sorted") |
| finally: |
| array.hide_partition() |
| |
| def demosort(array): |
| while 1: |
| for alg in [quicksort, insertionsort, selectionsort, bubblesort]: |
| randomize(array) |
| alg(array) |
| |
| |
| # Sort demo class -- usable as a Grail applet |
| |
| class SortDemo: |
| |
| def __init__(self, master, size=15): |
| self.master = master |
| self.size = size |
| self.busy = 0 |
| self.array = Array(self.master) |
| |
| self.botframe = Frame(master) |
| self.botframe.pack(side=BOTTOM) |
| self.botleftframe = Frame(self.botframe) |
| self.botleftframe.pack(side=LEFT, fill=Y) |
| self.botrightframe = Frame(self.botframe) |
| self.botrightframe.pack(side=RIGHT, fill=Y) |
| |
| self.b_qsort = Button(self.botleftframe, |
| text="Quicksort", command=self.c_qsort) |
| self.b_qsort.pack(fill=X) |
| self.b_isort = Button(self.botleftframe, |
| text="Insertion sort", command=self.c_isort) |
| self.b_isort.pack(fill=X) |
| self.b_ssort = Button(self.botleftframe, |
| text="Selection sort", command=self.c_ssort) |
| self.b_ssort.pack(fill=X) |
| self.b_bsort = Button(self.botleftframe, |
| text="Bubble sort", command=self.c_bsort) |
| self.b_bsort.pack(fill=X) |
| |
| # Terrible hack to overcome limitation of OptionMenu... |
| class MyIntVar(IntVar): |
| def __init__(self, master, demo): |
| self.demo = demo |
| IntVar.__init__(self, master) |
| def set(self, value): |
| IntVar.set(self, value) |
| if str(value) != '0': |
| self.demo.resize(value) |
| |
| self.v_size = MyIntVar(self.master, self) |
| self.v_size.set(size) |
| sizes = [1, 2, 3, 4] + range(5, 55, 5) |
| if self.size not in sizes: |
| sizes.append(self.size) |
| sizes.sort() |
| self.m_size = OptionMenu(self.botleftframe, self.v_size, *sizes) |
| self.m_size.pack(fill=X) |
| |
| self.v_speed = StringVar(self.master) |
| self.v_speed.set("normal") |
| self.m_speed = OptionMenu(self.botleftframe, self.v_speed, |
| "single-step", "normal", "fast", "fastest") |
| self.m_speed.pack(fill=X) |
| |
| self.b_step = Button(self.botleftframe, |
| text="Step", command=self.c_step) |
| self.b_step.pack(fill=X) |
| |
| self.b_randomize = Button(self.botrightframe, |
| text="Randomize", command=self.c_randomize) |
| self.b_randomize.pack(fill=X) |
| self.b_uniform = Button(self.botrightframe, |
| text="Uniform", command=self.c_uniform) |
| self.b_uniform.pack(fill=X) |
| self.b_distinct = Button(self.botrightframe, |
| text="Distinct", command=self.c_distinct) |
| self.b_distinct.pack(fill=X) |
| self.b_demo = Button(self.botrightframe, |
| text="Demo", command=self.c_demo) |
| self.b_demo.pack(fill=X) |
| self.b_cancel = Button(self.botrightframe, |
| text="Cancel", command=self.c_cancel) |
| self.b_cancel.pack(fill=X) |
| self.b_cancel.config(state=DISABLED) |
| self.b_quit = Button(self.botrightframe, |
| text="Quit", command=self.c_quit) |
| self.b_quit.pack(fill=X) |
| |
| def resize(self, newsize): |
| if self.busy: |
| self.master.bell() |
| return |
| self.size = newsize |
| self.array.setdata(range(1, self.size+1)) |
| |
| def c_qsort(self): |
| self.run(quicksort) |
| |
| def c_isort(self): |
| self.run(insertionsort) |
| |
| def c_ssort(self): |
| self.run(selectionsort) |
| |
| def c_bsort(self): |
| self.run(bubblesort) |
| |
| def c_demo(self): |
| self.run(demosort) |
| |
| def c_randomize(self): |
| self.run(randomize) |
| |
| def c_uniform(self): |
| self.run(uniform) |
| |
| def c_distinct(self): |
| self.run(distinct) |
| |
| def run(self, func): |
| if self.busy: |
| self.master.bell() |
| return |
| self.busy = 1 |
| self.array.setspeed(self.v_speed.get()) |
| self.b_cancel.config(state=NORMAL) |
| try: |
| func(self.array) |
| except Array.Cancelled: |
| pass |
| self.b_cancel.config(state=DISABLED) |
| self.busy = 0 |
| |
| def c_cancel(self): |
| if not self.busy: |
| self.master.bell() |
| return |
| self.array.cancel() |
| |
| def c_step(self): |
| if not self.busy: |
| self.master.bell() |
| return |
| self.v_speed.set("single-step") |
| self.array.setspeed("single-step") |
| self.array.step() |
| |
| def c_quit(self): |
| if self.busy: |
| self.array.cancel() |
| self.master.after_idle(self.master.quit) |
| |
| |
| # Main program -- for stand-alone operation outside Grail |
| |
| def main(): |
| root = Tk() |
| demo = SortDemo(root) |
| root.protocol('WM_DELETE_WINDOW', demo.c_quit) |
| root.mainloop() |
| |
| if __name__ == '__main__': |
| main() |