examples/pidigits.py

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