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Storage: What Goes Where in the Arrays

My conventions for storing the output of real and complex Fourier transforms follows those given in Numerical Recipes (www.nr.com) with one important exception, noted below. You can look there for a more detailed description of the arrangement, but this documentation contains all the information you should need to use the FFTEASY routines. Before I describe this storage scheme, though, I should point out the one difference between the output of FFTEASY and Numerical Recipes, which is that the Numerical Recipes routines require you to divide the output of their inverse transforms by the number of data points. FFTEASY does this division for you so that the result you get from the FFTEASY routines represents the correct value of the transform, forward or inverted. In other words if you take an array of data and run it through one of the FFTEASY routines forward and then inverted you will get back your original data, which is not true of the Numerical Recipes routines.



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This documentation was generated on 2003-09-30