Magnitude data
Computes the magnitude spectrum of the current data set so all peaks appear positive. Useful when data is not pure absorption phase. The magnitude spectrum is calculated as
SQRT( Re2 + Im2 )
where Re and Im refer to the Real and Imaginary parts of the complex number, respectively.
Below are shown a contour plot of part of the HMQC spectrum of codeine, and the slice through the methoxy peak, processed with MC as the last step. Compare to the same data processed with M2, below.
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An alternative to a Magnitude Calculation (MC). The power spectrum is calculated as
Re2 + Im2
where Re and Im refer to the Real and Imaginary parts of the complex number, respectively.
Below are shown a contour plot of part of the HMQC spectrum of codeine, and the slice through the methoxy peak. This was processed using M2 as the last step. Compare to the same data processed with MC, above.
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The M2 command actually does a calculation which converts a time domain signal directly to a power spectrum without the need for an FT. This will work properly only with standard complex data sets, not with real or Bruker TPPI data sets. This was done to speed up 2D processing.
This command takes the square root of the data points of both the reals and imaginaries. If the data points are negative the point is replaced with the negative of the square root of the negative of the points value.
Last updated 10/24/01.