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Extracting the real and imaginary parts

The previous section sneaked in a reference to the function `cmplx2r', in the hope that what it did was obvious. As the name is intended to imply, `cmplx2r' is the reverse of `r2cmplx', and generates a non-complex data structure whose data array is taken from the real part of the data in a specified complex data structure.

`cmplx2r' does not make any changes to the dimensions of the data array.

Analogous to `cmplx2r' are `cmplx2i' and `cmplx2m', which extract the imaginary part of the data and the modulus of the data. Usually, there will be little point in explicitly extracting the real part, since it is already available to most Figaro functions as described earlier. However, the file generated by `cmplx2r' will be smaller than the original file, since it will no longer contain the imaginary array, and this may be a point in its favour.



next up previous 78
Next: Operations on complex data
Up: FFT
Previous: Taking the Fourier transform

FIGARO A general data reduction system
Starlink User Note 86
Keith Shortridge, Horst Meyerdierks,
Malcolm Currie, Martin Clayton, Jon Lockley,
Anne Charles, Clive Davenhall,
Mark Taylor, Tim Ash, Tim Wilkins, Dave Axon,
John Palmer, Anthony Holloway and
Vito Graffagnino
2004 February 17
E-mail:ussc@star.rl.ac.uk

Copyright © 2008 Science and Technology Facilities Council