EXTRACT
[DISPLAY\]EXTRACT VarName [blc1 blc2 blc3 trc1 trc2 trc3]
Extract a subset of the image variable VarName and put it in the EXTRACTED
image variable.
Without argument, the region covered by the subset is defined by the SIZE,
CENTER and RANGE values. In this case, the EXTRACTED variable dimensions are
automatically derived from this values, and EXTRACTED can be bigger than the
actual cube defined by VarName. Areas not covered by the initial VarName are
filled out with the Blanking value of the VarName, or by zeros if VarName
has no blanking.
If the arguments blc1 to trc3 are specified, the subset corresponds to
VarName[blc1:trc1,blc2:trc2,blc3:trc3] of the image variable VarName. The
BLCi and TRCi values must correspond to a valid subset.