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Ian

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29 Aug 2014 FFT-based convolution Discrete convolution using FFT method Author: Bruno Luong

I am running 2014a on a machine with 192Gb of RAM and 20 cores. I am trying to convolute two vectors, one with 3,060,663 elements, the other with 693. The built-in conv took 0.06 seconds. convnfft filled the memory and then crashed the machine.

10 Mar 2014 Load HITRAN 2004+ Data Imports HITRAN molecular absorption data as raw and absorbance data. Author: Peter T. S. DeVore

For calculating your Voigt function, I highly recommend:

http://www.mathworks.com/matlabcentral/fileexchange/38787-faddeeva-package-complex-error-functions

it is both fast and accurate.

28 Feb 2014 Faddeeva Package: complex error functions C++ MEX plugins to compute error functions (erf, erfc, erfi, erfcx, Faddeeva, ...) of complex args Author: Steven G. Johnson

One update I would really like to see in this package is the derivative functions, at least for W(z). As pointed out in Zaghloul and Ali, the derivative functions of W(z) (equations 21-23) become numerically unstable near dV/dx = 0 (V=real(W(z)), at the peak of the Voigt function. This can cause problems when trying to compute analytical Jacobians for doing nonlinear fits of the Voigt function to optical spectra.

Since you are already using the Zaghloul and Ali algorithm in this region, it would be helpful to also use their method to output a function, say Faddeeva_dw(z) = dV/dx + i*dL/dx (L=imag(W(z)). The corresponding y derivatives can then be trivially computed.

27 Feb 2014 Faddeeva Package: complex error functions C++ MEX plugins to compute error functions (erf, erfc, erfi, erfcx, Faddeeva, ...) of complex args Author: Steven G. Johnson

Works as advertised and is extremely fast.

24 Feb 2014 National Instruments (NI) XML reader for Matlab Two functions: one for printing and one for reading into a struct an National Instruments XML file Author: John Paden

This is still a great submission, but I have found a bug either in the script or in LabVIEW 2009's XML implementation. If I create an XML file in LV containing only an array, usually I get a block that looks like this:

<Array>
<Name>Decimated Array</Name>
<Dimsize>800</Dimsize>
<DBL>
<Name></Name>
<Val>20.03500875218805</Val>
</DBL>
<DBL>
<Name></Name>
<Val>20.12253063265817</Val>
</DBL>
</Array>

But sometimes I get this instead:

<Array>
<Name>Decimated Array</Name>
<Dimsize>800</Dimsize>
<DBL>
<Name>Numeric</Name>
<Val>20.03500875218805</Val>
</DBL>
<DBL>
<Name>Numeric</Name>
<Val>20.12253063265817</Val>
</DBL>
</Array>

and when the script comes across the word 'Numeric', it thinks that it's no longer an array and over-writes the previous value.

In my copy, I've modified line 86 to read:

if isempty(name) || strcmp(name,'Numeric')

Since I'm new to using the XML file format with LV, I don't know how general this fix is going to be.

I still stand by my 5 stars, though.

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