how to control the index of the array

[2716jag]

im having a 2D 100 x 100 array which i want place a value in some  X x Y place.

Any suggestions ..?

-Jagan

[RavensFan]

Replace Array Subset.

[2716jag]

thanks buddy,

The array im using having the row limitation of 4096 and coloumn of 17000 and each cell having the limitation of 32bit value. But every time this much size is not required. how to create memory dynamically for this array.

Or any other option is there in labview.

[GerdW]

Hi jag,

an array of ~265MB should be ok for LabView on modern PCs... (as long as you don't create data copies!)

Either you create an array that big or you don't. Or you have to work on smaller arrays...

[2716jag]

In visual C++ there is an option like grid (which makes the array grow snd shrink dynamically)

Is there any option or tool available here?

[GerdW]

Hi jag,

you can use "build array" to "grow" an array and "array subset" to "shrink" it. But both function (may) produce data copies...

[2716jag]

hi GredW,

do you mean data copy is, using a local variable of that array to store the values or what exactly data copy is??

-Jagan

[GerdW]

Hi Jagan,

no, not "local variables".

LabView has to create data copies in memory for certain operations. You can recognize this by using menu entry Tools->Advanced->Show Buffer Allocations (LV7.1, may be different menu entry in LV8+)...

Let's take a typical "build array" operation: You wire a source array and a new element to append to this function. LabView has to create a copy of the source array in a bigger memory space to allow appending of the new element, hence "data copy"/buffer allocation...

[2716jag]

Hi GredW

Im using lots of local variable, so it may cause the slower exection of my application isn't it? Ok

Im using LabVIEW 7.0 Express, in that how to see that data copies created?

[GerdW]

Hi Jag,

using "lots of locals" is considered bad programming style usually

You should find that "show buffer allocations" in the same place in LV7. I'm not sure, but maybe it's not included in base versions...