expand approximately reverses the effect of collapse. i.e. it takes an Ultracam frame consisting of null or 1D windows and expands them by repeating the data across the frame to make it match a reference image. The resulting frame can then be used to divide into, subtract from etc the reference image. A complication is that one or more of the windows that result from collapse may have zero dimension. They are not eliminated in order to keep the number and order of windows the same. However, they will be grown back as well. In this case you must think what value you want them to have. If you intend to add or subtract the expanded frame, you probably want to grow the data back with zeroes, while for multiplication or division you probably want to use 1. You will be prompted for the value to use.
expand input template value output
| input | --- | Input frame to be expanded |
| template | --- | Frame defining the sizes of the expanded windows. The windows will have to match in their lower-left corners and non-collapsed dimensions. |
| value | --- | The value to use when expanding null windows; see above for a discussion of why this is needed. |
| output | --- | Output, a frame in which one of the dimensions of the windows is collapsed to 1. |
This command is a member of the classes: Arithematic, Manipulation, Programs, Spectra.
Author: T.R. Marsh
Created: 08 November 2006
Revised: 19 November 2006