Data update

Task/Factorial/REXX/factorial-4.rexx

@@ -0,0 +1,4 @@
+call time('r')
+numeric digits 999999999
+a = 10/3
+say length(a) time('e')

Task/Factorial/REXX/factorial-5.rexx

@@ -0,0 +1,67 @@
+include Settings
+
+say version; say 'Factorial'; say
+p = '10 20 52 104 208 416 1e3 1e4 1e5 1e6 1e7 1e8'
+call Val 100
+p = '10 20 52 104 208 416 1e3 1e4 1e5 1e6'
+call Dig 100
+call Dig 1000
+call Dig 3000
+p = '10 20 52 104 208 416 1e3 1e4 1e5'
+call Dig 40000
+call Dig 500000
+p = '10 20 52 104 208 416 1e3 1e4'
+call Dig 5000000
+exit
+
+Val:
+call Time('r')
+arg d
+numeric digits d; fact. = 0
+say 'Precision is' d 'digits'
+do i = 1 to Words(p)
+   call Time('r');f = Word(p,i); say f'!' '=' Fact(f) '('Format(Time('e'),,3)'s)'
+end
+say
+return
+
+Dig:
+call Time('r')
+arg d
+numeric digits d; fact. = 0
+say 'Precision is' d 'digits'
+do i = 1 to Words(p)
+   call Time('r'); f = Word(p,i); h = Fact(f)
+   parse var h 'E' e
+   if e = '' then
+      say f'!' 'has exact' Length(h) 'digits' '('Format(Time('e'),,3)'s)'
+   else
+      say f'!' 'has about' e+1 'digits' '('Format(Time('e'),,3)'s)'
+end
+say
+return
+
+Fact:
+/* Factorial = n! */
+procedure expose fact.
+arg x
+/* Current in memory? */
+if fact.factorial.x <> 0 then
+   return fact.factorial.x
+/* Previous in memory? */
+w = x-1
+if fact.factorial.w = 0 then do
+/* Loop cf definition */
+   y = 1
+   do n = 2 to x
+      y = y*n
+   end
+   fact.factorial.x = y
+end
+else
+/* Multiply */
+   fact.factorial.x = fact.factorial.w*x
+return fact.factorial.x
+
+include Functions
+include Abend