NUMFACTORS Name
NUMFACTORS Purpose
Gives the number of factors of a number.
Category
Calling Sequence
nf = numfactors(x) Inputs
x = number to factor. in
Keyword Parameters
Keywords
/QUIET do not list factors.
PROGRESS=n Indicate progress every n values (for arrays).
Outputs
nf = number of factors of x. out
Does not include 1 and x. Common Blocks
Notes
Note: let the factors of x be described by p, the array
of prime factors, and n, the count of each prime factor.
The i'th prime factor, p(i), may occur from 0 to n(i)
times (that is, up to n(i)+1 times) in any given factor
of x. The total number of factors is the product of the
maximum number of occurences of each prime factor.
For example: let n = [3,1,1], then the total number of
factors, nf = 4*2*2. To include 1 and x add 2.
(From a conversation with Robert Jensen, JHU/APL.)
See also prime, factor, print_fact.
Modification History
R. Sterner, 25 Oct, 1990
R. Sterner, 26 Feb, 1991 --- Renamed from num_factors.pro
R. Sterner, 5 Feb, 1993 --- Modified to handle arrays.
R. Sterner, 2000 Jan 06 --- Added /QUIET.
R. Sterner, 2004 Jul 27 --- Fixed a typo in help text.
R. Sterner, 2010 Jun 09 --- Converted arrays from () to [].
Copyright (C) 1990, Johns Hopkins University/Applied Physics Laboratory
This software may be used, copied, or redistributed as long as it is not
sold and this copyright notice is reproduced on each copy made. This
routine is provided as is without any express or implied warranties
whatsoever. Other limitations apply as described in the file disclaimer.txt.