Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
Sven Ohmann writes: > in the code below I want to use the variable voxel_a0 globally. That > means, when I try after compilation (successful) to run the program I > got the message: > > variable is undefined : voxel_a0 > > In principle I want that after starting the program after pressing the > 'apply_button' (eventhandler=3Dapplydata_event) the variables should be > stored globally in the structure pState, so that when proceeding the > program in the subprogram efgalc1_computedim I want to use them again, > and later on in other functions or subprograms as well. Any idea ? The variable isn't created yet when you are storing it in your state pointer. It is only created *after* the program runs. So, when you create the state pointer you have to put "dummy" data there to hold the place for the real data to be stored there later. I typically store something there that I would recognize as "not filled yet". For integers this might be the number -999, for example. For floating point numbers is might be !Values.F_NAN. If you have a pointer field that you don't *know* how to fill, or if what you are going to fill it with will vary in size or type, then, of course, you "hold the space" with a null pointer. Cheers, David -- David Fanning, Ph.D. Fanning Software Consulting, Inc. Coyote's Guide to IDL Programming: http://www.dfanning.com/ Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Sven Ohmann writes: > in the code below I want to use the variable voxel_a0 globally. I forgot to mention this in my last post, but here is an article that you might want to read to improve your IDL programs even more http://www.dfanning.com/tips/namefiles.html Cheers, David -- David Fanning, Ph.D. Fanning Software Consulting, Inc. Coyote's Guide to IDL Programming: http://www.dfanning.com/ Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Thank you very much for your help, it worked!!! I am going to read the article today in the evening regards sven David Fanning wrote: > Sven Ohmann writes: > >> in the code below I want to use the variable voxel_a0 globally. > > I forgot to mention this in my last post, but here is > an article that you might want to read to improve your > IDL programs even more > > http://www.dfanning.com/tips/namefiles.html > > Cheers, > > David > > -- > David Fanning, Ph.D. > Fanning Software Consulting, Inc. > Coyote's Guide to IDL Programming: http://www.dfanning.com/ > Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Thank you very much for your help,the program worked!! I am going to read the article today in the evening regards sven David Fanning wrote: > Sven Ohmann writes: > >> in the code below I want to use the variable voxel_a0 globally. > > I forgot to mention this in my last post, but here is > an article that you might want to read to improve your > IDL programs even more > > http://www.dfanning.com/tips/namefiles.html > > Cheers, > > David > > -- > David Fanning, Ph.D. > Fanning Software Consulting, Inc. > Coyote's Guide to IDL Programming: http://www.dfanning.com/ > Sepore ma de ni thui. ("Perhaps thou speakest truth.")