How 'local' are local Variables?

I avoid local variables at any price so don't have much experence with them. Local only 'local' to the subvi in what they are or if you have used the local variable from sale in several subvi in the same program would be that they all share the same varaible?

I got the task of determining a LabView program that we had subcontracted out. The device, on which he works has three identical modules that are used for the profile and discharge profiles for different types of batteries. In any case, the program has a bug in it where all three on screen V / I charts show the same V / I have curves.

My original thought CD was the subcontractor got the program works on a module, then reproduced the code to the other two. But did not take a new graphics or was referencing the V / I module of measure 1 in charts 2 and 3. First glance on the code it looked like it should work fine.

Digging deeper, I see the contractor makes this sup - vi to build the cluster for a waveform graph. In this sub - vi he used a table variable local, called "local".

When he repeated this for the other two modules, he used the same variable local "local array. Since all three "programs" (one for each module) operate within a larger loop would not all be read and write to the same variable local "local array?

I have attached the origonal sub - vi (V_WFM.vi) and one of my replacements (V_Wave_1.vi), I've made three copies of my vi and each module will get its own sub - vi.

I'm not doing correctly?


Tags: NI Software

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