examples/pidigits.py

   1 import sys
   2 sys.path.append("..")
   3 from sympy.numerics import *
   4 from sympy.numerics.utils_ import *
   5 from sympy.numerics.constants import pi_float
   6 import math
   7 from time import clock
   8
   9 def display_fraction(digits, skip=0, colwidth=10, columns=5):
  10     perline = colwidth * columns
  11     printed = 0
  12     for linecount in range((len(digits)-skip) // (colwidth * columns)):
  13         line = digits[skip+linecount*perline:skip+(linecount+1)*perline]
  14         for i in range(columns):
  15             print line[i*colwidth : (i+1)*colwidth],
  16         print ":", (linecount+1)*perline
  17         if (linecount+1) % 10 == 0:
  18             print
  19         printed += colwidth*columns
  20     rem = (len(digits)-skip) % (colwidth * columns)
  21     if rem:
  22         buf = digits[-rem:]
  23         s = ""
  24         for i in range(columns):
  25             s += buf[:colwidth].ljust(colwidth+1, " ")
  26             buf = buf[colwidth:]
  27         print s + ":", printed + colwidth*columns
  28
  29 def calculateit(func, base, n, tofile):
  30     Float.setprec(100)
  31     intpart = small_numeral(int(float(func())), base)
  32     if intpart == 0:
  33         skip = 0
  34     else:
  35         skip = len(intpart)
  36     Float.setprec(int(n*math.log(base,2))+10)
  37     print "Step 1 of 2: calculating binary value..."
  38     t = clock()
  39     a = func()
  40     step1_time = clock() - t
  41     print "Step 2 of 2: converting to specified base..."
  42     t = clock()
  43     d = bin_to_radix(a.man, -a.exp, base, n)
  44     d = fixed_to_str(d, base, n)
  45     step2_time = clock() - t
  46     print "\nWriting output...\n"
  47     if tofile:
  48         out_ = sys.stdout
  49         sys.stdout = tofile
  50     print "%i base-%i digits of pi:\n" % (n, base)
  51     print intpart, ".\n"
  52     display_fraction(d, skip, colwidth=10, columns=5)
  53     if tofile:
  54         sys.stdout = out_
  55     print "\nFinished in %f seconds (%f calc, %f convert)" % \
  56         ((step1_time + step2_time), step1_time, step2_time)
  57
  58 def interactive():
  59     print "Compute digits of pi with SymPy\n"
  60     base = input("Which base? (2-36, 10 for decimal) \n> ")
  61     digits = input("How many digits? (enter a big number, say, 10000)\n> ")
  62     tofile = raw_input("Output to file? (enter a filename, or just press enter\nto print directly to the screen) \n> ")
  63     if tofile:
  64         tofile = open(tofile, "w")
  65     global_options["verbose"] = True
  66     global_options["verbose_base"] = base
  67     calculateit(pi_float, base, digits, tofile)
  68     raw_input("\nPress enter to close this script.")
  69
  70 interactive()