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I do not really like to use the built in command FACTORS when I would like to know the factors of a integer number in real format. FACTORS would require some flags to be set plus real to integer conversion.

Sure when I have massive needs, then FACTORS is better, but otherwise I'd like to have a more handy routine.

A quick idea is the one below, but do you know any one else that coded something more robust and fast? Or maybe a MathExt library containing a substitution of FACTORS?

Requirements:
input: an integer or an integer in real form (so with the dot at the end), flag -3 and -105 set or unset, does not matter.
output: the factors of the input number (integers in real or integer form)

Code:

factorsR

  \<<

    {} "resultList" DROP

    2 "possibleDivisor" DROP

    0 "divisorFound" DROP

    \->

    @input

    inputNumber

    @local var

    resultList

    possibleDivisor

    divisorFound

    \<<

      WHILE

        inputNumber ISPRIME? NOT

        inputNumber 1 >

        AND

      REPEAT

        2 'possibleDivisor' STO

        0 'divisorFound' STO

        WHILE

          divisorFound 0 ==

        REPEAT

          IF

            inputNumber possibleDivisor MOD 0 ==

          THEN

            1 'divisorFound' STO

            'resultList' possibleDivisor STO+

            inputNumber possibleDivisor / 'inputNumber' STO

          ELSE

            possibleDivisor NEXTPRIME 'possibleDivisor' STO

          END

        END

      END

      'resultList' inputNumber STO+

      resultList

    \>>

  \>>

(09-10-2017 10:02 AM)pier4r Wrote: [ -> ]I do not really like to use the built in command FACTORS when I would like to know the factors of a integer number in real format. FACTORS would require some flags to be set plus real to integer conversion.

Hi Pier...
Another way :

Code:

My new Factors command :

«

 PUSH   @ save system flags

  DUP 

   RAD -3 CF  R->I  FACTORS 

  SWAP TYPE NOT { I->R } IFT

 POP @ Restaure system flags

»

If i'm not wrong it's OK with your requirements:
input: an integer or an integer in real form (so with the dot at the end), flag -3 and -105 set or unset, does not matter.
output: the factors of the input number (integers in real or integer form)
No change of the flags setup and angle mode

pier4r

Gilles59