chore: import upstream snapshot with attribution

demo/pidigits.py

@@ -0,0 +1,82 @@
+"""
+Calculate digits of pi. This module can be run interactively with
+
+    python pidigits.py
+
+"""
+
+import math
+import sys
+from time import perf_counter
+
+from mpmath.libmp.libelefun import pi_fixed
+from mpmath.libmp.libintmath import bin_to_radix, numeral
+
+
+def display_fraction(digits, skip=0, colwidth=10, columns=5):
+    perline = colwidth * columns
+    printed = 0
+    for linecount in range((len(digits)-skip) // (colwidth * columns)):
+        line = digits[skip+linecount*perline:skip+(linecount+1)*perline]
+        for i in range(columns):
+            print(line[i*colwidth : (i+1)*colwidth], end=' ')
+        print(":", (linecount+1)*perline)
+        if (linecount+1) % 10 == 0:
+            print()
+        printed += colwidth*columns
+    rem = (len(digits)-skip) % (colwidth * columns)
+    if rem:
+        buf = digits[-rem:]
+        s = ""
+        for i in range(columns):
+            s += buf[:colwidth].ljust(colwidth+1, " ")
+            buf = buf[colwidth:]
+        print(s + ":", printed + colwidth*columns)
+
+def calculateit(base, n, tofile):
+    intpart = numeral(3, base)
+    skip = 1
+    if base <= 3:
+        skip = 2
+
+    prec = int(n*math.log(base,2))+10
+
+    print("Step 1 of 2: calculating binary value...")
+    t = perf_counter()
+    a = pi_fixed(prec, verbose=True, verbose_base=base)
+    step1_time = perf_counter() - t
+
+    print("Step 2 of 2: converting to specified base...")
+    t = perf_counter()
+    d = bin_to_radix(a, prec, base, n)
+    d = numeral(d, base, n)
+    step2_time = perf_counter() - t
+
+    print("\nWriting output...\n")
+
+    if tofile:
+        out_ = sys.stdout
+        sys.stdout = tofile
+    print("%i base-%i digits of pi:\n" % (n, base))
+    print(intpart, ".\n")
+
+    display_fraction(d, skip, colwidth=10, columns=5)
+    if tofile:
+        sys.stdout = out_
+    print("\nFinished in %f seconds (%f calc, %f convert)" % \
+        ((step1_time + step2_time), step1_time, step2_time))
+
+def interactive():
+    print("Compute digits of pi with mpmath\n")
+    base = input("Which base? (2-36, 10 for decimal) \n> ")
+    digits = input("How many digits? (enter a big number, say, 10000)\n> ")
+    tofile = input("Output to file? (enter a filename, or just press " \
+        "enter\nto print directly to the screen) \n> ")
+    if tofile:
+        tofile = open(tofile, "w")
+
+    calculateit(int(base), int(digits), tofile)
+    input("\nPress enter to close this script.")
+
+if __name__ == "__main__":
+    interactive()