Measurement Studio memory problem

[M.Koot]

I'm using the IIRFiltering function of the CWDSP package. I have to process large ammounts of data at once (over 265 MB). The input data is in integer format, this is good enough and is in fact a demand to keep the memory usage low. The function seems to take this format fine.
But the problem now is that the IIRFilter only seems to return data in variant format which is unacceptably large (8 times as large!).
This variant is no option while it crashes my system due to memory overload.
Is there any way that the IIRFiltering module can output the data in integer format? Or is there any other way to keep the memory usage of the function low?
Thanks.

[drohacek]

Unfortunately for your application, this is just the way that the control works. There is no way to change the data type that the control returns.

I can think of a couple of ways that you might be able to work around this issue. If you own Measurement Studio, you could use the C++ tools to create a DLL that calls the appropriate CNiIIRCascadeFilter function. The C++ tools return the values as an array of doubles. This would be only twice as large as your integer data. The underlying National Instruments analysis library operates on doubles - we do not provide an algorithm that operates on integers - so this is as small as you will get with our tools.

Another option is to decimate your data (use CWDSP.Decimate) before you attempt to filter it. Whether this
will yield accurate enough results for you really depends on your application.

If neither of these options is acceptable, you might need to consider hardware alternatives.

[M.Koot]

Thank you for your suggestions. I was questioning myself though if it wouldn't be possible for me to receive the source code of the IIRFiltering function, so I might could adjust the output datatype myself? I have bought the enterprice package and thus license, maby this would be a possibility?