[SOLVED]Assign Expression To A Numeric Parm?

[Atom]

Hi All,

I am trying to assign an expression to a parameter using python. I want to link two objects together.

I get a type error "Cannot set a numeric parm to a non-numeric value."

I understand I am trying to assign a string to a number field, but the string contains the expression.

Is this possible in using the current python in Houdini 15.5?

Here is my code so far...

trc_source = "/obj/trc"
trc_target = "/obj/angela_1_T_pose_fbx"
lst_source_blocks = ["Root"]
lst_target_blocks = ["hip_To_abdomen"]

for (i,name) in enumerate(lst_source_blocks):
    source_candidate = "%s/%s" % (trc_source, name)
    n = hou.node(source_candidate)
    if n != None:
        target_candidate = "%s/%s" % (trc_target, lst_target_blocks[i])
        m = hou.node(target_candidate)
        if m != None:
            s = '`ch("%s/%s/tx")`' % (trc_source,name)
            m.parm("tx").set(s)
	

Edited July 14, 2016 by Atom

[graham]

You can use hou.Parm.setExpression() http://www.sidefx.com/docs/houdini15.5/hom/hou/Parm#setExpression to set an expression.

Alternatively you can actually set parms to other parms and it will automatically create channel references for you:

tx = hou.parm("/obj/geo1/tx")
ty = hou.parm("/obj/geo1/ty")
ty.set(tx)

 

[Atom]

Thanks Grahm, that works!

m.parm("tx").setExpression(s)