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VEXpression Problem

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Hi everyone,


I have a big issue about exporting data from vexpression context.


I used vexpression to set the velblend parameter in the "popadvectbyvolume" node. So I can advect particles differently along time.

But I'm not sure what result number I have, so I want to export this value to check it out in the geometrie spreadsheet.


I found this line in Houdini Help: export float @mytest = 0;


So here is my code:


#use a parameter to set the velblend

velblend = @activate;


#use a count to set the velblend differently when I want to
if(@count >= 3) { velblend = 1/((@count/3)*5); }


#want to export the final result to debug
export float @velblend;



My popnetwork works fine (my particles get different vel along time) and I don't have any error.

But when I check the velblend attribut in spreadsheet, it stay to 0.0



So I tried different syntax like:


export float @debug = velblend;

export float @debug = @velblend;

export float @parm_velblend;


But each time I had an error : "velblend" is not a valid default for this prototype...




I'm getting crazy right now!! :wacko:

If someone could have an idea, it could be great! :D


Thx a lot.



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you need to initialize export variable to constant value, it can't be another variable

and then later you can assign a varying value to it

export float @velblend = 0;

velblend = @activate;
if(@count >= 3) { velblend = 1/((@count/3)*5); }

@velblend = velblend;

in a cleaner example:

export float @debug = 0;

f@debug = rand(@id);
Edited by anim

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It works perfectly :D :D


Thx a lot anim!

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