[bb] Factor Calculator by schilcote [ 1+ years ago ]

[BlitzBot]

Title : Factor Calculator
Author : schilcote
Posted : 1+ years ago

Description : This function calculates the factors of any number you pass to it. It then stores the numbers in a memory bank (I think, I've had it so long I've forgotten how to use it) whick you peekint (is that in B+?) or equivalent to retrive.

Code :

Code (blitzbasic) Select Expand

Global FCBnk
Function factor (Num)
DebugLog"Factor calculating function called"
FCBnk=CreateBank (1024)
Fact2=1
Repeat
Rep=Rep+1
Fact=Fact+1
;Detect need for change in second number
If Fact=num Then
Fact2=Fact2+1
Fact=1
EndIf
DebugLog "Checking For Factor, "+Fact+" * "+Fact2
;Detect factor
Test=Fact*Fact2
If Test=Num Then
PokeInt FCBnk,Ofst,Fact
DebugLog "Factor Calculated,"+Fact
ofst=ofst+3
EndIf
Until (Test=Num And Fact=1)
DebugLog"Factor of 1 reached, end computation."
End Function

Comments :


Dabhand(Posted 1+ years ago)

 Nice... I'll give this 10/10 since the author stated 'I think, but I've forgotten' in the description! ;)Never seen that one before! :DDabz


schilcote(Posted 1+ years ago)

 Really? It took me 30 seconds to make. The factor calculator program is alot better. I updated that one a few times, and never really paid attention to this. If anyone asks I can throw the program at them. Maybe it's engine can be used for something else. Like a function.


Matty(Posted 1+ years ago)

 Your original code will not work for the following reasons, and could be written better:1. variable Rep <- never referenced aside from incrementing by 1 each iteration2. Bank is only 1024 bytes long, so you are limited to having a rather limited number of factors, and wasting memory (albeit not much) if it is not used3. You are incrementing the offset in the bank by 3 bytes, thus overwriting the last byte of each integer which is 'poked'.A simpler, perhaps more elegant method, would be to do as follows:It could be made smarter, such as using a variable data size 1 byte for factors<256, 2bytes for factors<65536 else 4 bytes

Code Select Expand

Function GetFactors(Num)
if Num = 0 then return
bank=createbank() ; no size initially, we will resize it as we fill it
offset=0
for factor = 1 to Num
if Num Mod Factor = 0 then
ResizeBank(bank,banksize(bank)+4)
PokeInt bank,offset,factor
offset=offset + 4 ;size of integer
endif
next
return bank ;no need for a global bank as we will return it here and the user can then do what they want with it.
End Function