Simplified PowerSpectrums _getAmplitudes() method when compressing the frequency range over the sheet dimensions. Changed PowerSpectrums frequency index spacing to be a private param, reduced the number of points it calculates to the sheet dimensions.
Simplified PowerSpectrums _getAmplitudes() method when compressing the frequency range over the sheet dimensions. Changed PowerSpectrums frequency index spacing to be a private param, reduced the number of points it calculates to the sheet dimensions.

git-svn-id: 1090b387d452580804210ae271d3c35ba515bde4@11598 0ce056cd-c842-0410-9ff1-d0633a95805a

jesuscript/topo-mpi,jesuscript/topo-mpi,jesuscript/topo-mpi,jesuscript/topo-mpi,jesuscript/topo-mpi