Converting to and from OpenMx

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Picture of user. mspiegel Joined: 07/31/2009

equivalent of DROP in OpenMx interface

There's been some discussion among the beta testers to support setting a free parameter to a fixed parameter across an entire model, or setting a fixed parameter to a free parameter across an entire model. Here's a function in R that will accomplish the transformation. The 'model argument is a MxModel object. The 'labels' argument is a vector of parameter names. The 'free' argument is either a NA or a single TRUE or FALSE. The 'value' argument is either a NA or a single numeric value.
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Picture of user. mspiegel Joined: 07/31/2009

converting Mx 1.0 algebras

I've written a python script that converts Mx 1.0 algebra expressions into OpenMx. The script is located in the subversion repository at trunk/inst/tools/mxAlgebraParser.py (in the next binary release 0.1.6 you will find this file in your OpenMx installation in the directory tools/mxAlgebraParser.py). You will need python installed on your machine, and the PLY library (Python Lex-Yacc library). If you have easy_install on your machine, run "sudo easy_install ply" for painless install.
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Picture of user. mspiegel Joined: 07/31/2009

tighter: unary minus or inverse/transpose?

I don't happen to have Mx 1.0 installed on this machine. Which operator binds tighter, unary minus or inverse/transpose? I don't know what is the "correct" answer, but I figure someone could just try -A~ and see which operator is applied first.
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Picture of user. pdeboeck Joined: 08/04/2009

Automatic Conversion of Scripts?

Does the current version of OpenMx allow for automatic conversion of scripts from other programs (e.g. LISREL)? For some reason I thought you were toying with this idea.
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Picture of user. Steve Joined: 07/30/2009

Welcome to the OpenMx conversions forum

This forum is for people who either are using another package and are wondering how to convert their scripts to OpenMx, or perhaps you've written a script in OpenMx and you'd like to convert it to use some other software. Not every software package can run every model, so inevitably there will also be discussions about software limitations. But please be respectful of each other's favorite software choices.