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20030411: Selecting variables from multiple files

John-


In the ability to use multiple files for variables in display a graph, I
tried to use some arbitrary function = f(TA, QV) and in designing the formula (in this case, I just used: (TA + QV) ), the following display came up allowing me to choose which variable (from the desired file) that I'd like to use... (that's a good design)...
TA QV
C\IDV_Stuff\vis5d_stuff\MET_CROSS_2.v5d C\IDV_Stuff\vis5d_stuff\MET_CROSS_2.v5d 
       3D grid                                  3D grid
          TA                                       TA
QV QV C\IDV_Stuff\vis5d_stuff\MET_CROSS_2BB.v5d C\IDV_Stuff\vis5d_stuff\MET_CROSS_2BB.v5d 
       3D grid                                  3D grid
          TA                                       TA
QV QV 


But when I wanted to utilize the arbitrary function: (TA + TA) and use
the first "TA" from one file and use the second "TA" from the other file, say, the IDV choice came up with : 
   TA
C\IDV_Stuff\vis5d_stuff\MET_CROSS_2.v5d 3D grid TA QV
C\IDV_Stuff\vis5d_stuff\MET_CROSS_2BB.v5d 3D grid TA QV 
Thus, I wasn't able to select a variable (TA in this case) from one file
and also select the second TA (in "(TA + TA)"), from a second file...
I wonder if there shouldn't be something of this nature display: 
   TA (for 1st occurrence of TA in "TA + TA")   TA  (for 2nd occurrence
of TA in "TA + TA") C\IDV_Stuff\vis5d_stuff\MET_CROSS_2.v5d C\IDV_Stuff\vis5d_stuff\MET_CROSS_2.v5d 
       3D grid                                  3D grid
          TA                                       TA
QV QV
C\IDV_Stuff\vis5d_stuff\MET_CROSS_2BB.v5d C\IDV_Stuff\vis5d_stuff\MET_CROSS_2BB.v5d 
       3D grid                                  3D grid
          TA                                       TA
QV QV 

This would allow the user to pick the TA of whichever file they wanted
for each or any of the TAs in the formula... So, with this type of system, it seems as 
though when the variables are not alike (ie.: "TA + QV"),  one can
utilize the feature of using various variables from different files but
if the formula had all like variables, (ie.: "TA + TA"), one may not be
able to select the appropriate file for each "TA", in this case, to use
in graphing the results.... 

The idea was that if a variable is used more than once in a formula,
it was assumed to be the same variable (ie. T-TD/T).  So, if you
had the variable in the formula 10 times, you didn't have to
select it 10 times. In the meantime, you could...


(There may be better ways to accomplish this problem, Don, but the main
thing (right now) is just  to make you aware of this problem...)....


....create a formula (D1+D2) (or TA1 + TA2 - anything to make
them different) and it should allow you choose arbitrary
values.  This way you could create an arbitrary formula
for addition and then select whatever you want to add.
Having the variable names does not give you automatic
selection in the datatree anyway, so using generic names
is just as well.

Don Murray
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