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  DIMENSIONS

Changes the size of program arrays and allows the ``memory'' arrays and variance arrays to be used or not. The user is prompted for the new size of program arrays. WARNING: this operation destroys any data that was already present in the current data array or in the memory. The user should save any data (OUTPUT DATA) before performing this operation. If the ``memory'' arrays are not created many of the menu commands with be disabled. Similarly certain commands require that the variance arrays exist so cannot work without defined variance arrays.

As with all other operations which allocate memory this may fail owing to system limits. If this does fail trying to continue regardless will almost certainly lead to false results or further errors. See Section 3.2, Page [*].

This example shows the program dialogue when the DIMENSIONS is used to create program arrays which are 1000 $\times$ 1000 elements, with ``memory'' arrays and variance arrays.

Main menu: ENTER COMMAND [INPUT DATA]:dim
ARRAY X DIMENSION (Range: 1 to 100000) [500]:1000
ARRAY Y DIMENSION (Range: 1 to 100000) [500]:1000
CREATE MEMORY [YES]:
CREATE VARIANCE ARRAYS [NO]:yes

This example shows the program dialogue when the DIMENSIONS is used to create program arrays which are 2000 $\times$ 2000 elements, but without ``memory'' arrays nor variance arrays to reduce computer memory usage.

Main menu: ENTER COMMAND [INPUT DATA]:dim
ARRAY X DIMENSION (Range: 1 to 100000) [1000]:2000
ARRAY Y DIMENSION (Range: 1 to 100000) [1000]:2000
CREATE MEMORY [YES]:n
CREATE VARIANCE ARRAYS [YES]:n


next up previous contents index
Next:   DISPLAY LIMITS Up: The KEYBOARD INTERFACE: Command Previous:   DIFFRACTION PATTERN
Andrew Hammersley
2004-01-09