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+--- Thread: 50g. Substitution of the FACTORS command (/thread-9033.html)
50g. Substitution of the FACTORS command - pier4r - 09-10-2017 10:02 AM
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
\>>
\>>RE: 50g. Substitution of the FACTORS command - Gilles59 - 09-10-2017 10:21 AM
(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