Hi

Can someone show me how to use setAttr with matrix attribute in python please.

I have tried various things like (with an without the type="matrix")

cmds.setAttr("pSphere1.myMatrix", 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 , type="matrix")
cmds.setAttr("pSphere1.myMatrix", (0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15) , type="matrix")
cmds.setAttr("pSphere1.myMatrix",[[1.0, 0.0, 0.0, 0.0], [0.0, 1.0, 0.0, 0.0], [0.0, 0.0, 1.0, 0.0], [1.0, 2.0, 3.0, 1.0]] , type="matrix")

mat = cmds.getAttr("pSphere1.test")
cmds.setAttr("pSphere1.myMatrix", mat , type="matrix")

but nothing seems to work.

Is this possible at all?

Thanks

Rob

Hmm.  Nope.  It’s not possible.  I tried everything I can think of, too.  I’ve submitted this as a bug, because this syntax really should work:

cmds.setAttr("pSphere1.myMatrix", (0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15) , type="matrix")

You can get by for now by importing the maya.mel module and calling the Mel setAttr from python that way…
search here for “maya.mel” for the example:
( http://download.autodesk.com/us/...al&file=Using_Python.html )

-Tony

Hi,

Yeah we went for the maya.mel route in the end too.  Of course its not great, as in our situation we want to set the matrix values from a previous python calculation.  This means we need to convert our values to strings first which means we lose accuracy.

I guess a ‘hack’ around the accuracy problem would be to prehaps create a double array attribute as well.  From python set the doubleArray attribute values (I am guessing that works unlike the matrix!) and then run a mel script which does a getAttr to get the doubleArray into a mel float array and then sets the matrix attribute.  Somewhat unelegant though (as well as slow!).

Anyway thanks for the reply

Rob

like this:
cmds.setAttr( ‘sphereShape.weights[0:6]’,1, 1, 2, 1, 1, 1, 2,size=7)

Sorry that should have been a reply not a comment :-)