It looks like you can't do that with a function...
Recursion is not handled gracefully by Codesys.
The closest option here is to use a function block as:
FUNCTION_BLOCKfb_RecursiuVAR_INPUTi : INT :=0;END_VARVAR_OUTPUTiResult : INT :=0;END_VARVAREND_VAR-----------------------------------------------IF(i<1)THENi :=0;ELSEi :=i-1;THIS^();END_IFiResult :=i;
And call it like this:
fbRecursiu(i:=iStart,iResult=>iResult);
That could be solved the day functions can be pointed by pointers... or when recursion worked as expected...
Hope this helps...
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I had not thought on this possibility, use an Fb. I will have it in mind.
At the moment I had solved my problem with an for loop. But sometimes recursion is the most elegant solution.
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Anonymous
-
2017-07-01
Originally created by: scott_cunningham
One word of caution - Recursion can spell trouble for stack size and other "behind the scenes" mechanisms. If you are dealing with Machine controllers and time sensitive field uses where their number one job is to not crash the whole machine, recursive solutions can be "risky" (just like for/next loops).
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Hi all.
Do you know if it is possible to call a function from himself in st.
If yes, how.
If I do:
Funtion factorial:lreal
Var_input
Value:lreal
End_var
If(value<2) then
Factorial:=1
Else
Factorial:=value*factorial(value-1)
End_if
Returns an error
Hi Josep!
It looks like you can't do that with a function...
Recursion is not handled gracefully by Codesys.
The closest option here is to use a function block as:
And call it like this:
That could be solved the day functions can be pointed by pointers... or when recursion worked as expected...
Hope this helps...
Thanks Joan.
I had not thought on this possibility, use an Fb. I will have it in mind.
At the moment I had solved my problem with an for loop. But sometimes recursion is the most elegant solution.
Originally created by: scott_cunningham
One word of caution - Recursion can spell trouble for stack size and other "behind the scenes" mechanisms. If you are dealing with Machine controllers and time sensitive field uses where their number one job is to not crash the whole machine, recursive solutions can be "risky" (just like for/next loops).