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LOAD

Ref Sec18.

LOAD

/I/J/K/L/M/N /X/Y/Z/T/E/F /D /NAME /PERMANENT /TEMPORARY

Loads a variable or expression into memory.

yes? LOAD[/qualifiers] [expression_1 , expression_2 , ...]

Loading may speed execution of later commands that will require the loaded data. Often it is helpful to LOAD a large region of data encompassing several small regions in which the analysis will be pursued.

Load interacts with the current context exactly as other "action" commands CONTOUR, PLOT, SHADE, VECTOR, LIST, etc. do.

Any change to existing variable definitions will cause Ferret to clear memory for user-defined variables that may have been loaded. This ensures that the state of memory does not become out of date with the current tree of variable definitions. If file data has been loaded it is unaffected by changes to user-defined variables.

Parameters

Expressions may be any valid expression. See the chapter "Variables and Expressions", section "Expressions" for a definition of valid expressions. If multiple variables or expressions are specified they are treated in sequence. The expression(s) will be inferred from the current context if omitted from the command line.

Command qualifiers for LOAD:

LOAD/I=/J=/K=/L=/M=/N=/X=/Y=/Z=/T=/E=/F=

Specifies value or range of axis subscripts (I, J, K, L, M, or N), or axis coordinates (X, Y, Z, T, E, or F) to be used when evaluating the expression(s) being loaded.

LOAD/D=

Specifies the default data set to be used when evaluating the expression(s) being loaded.

LOAD/NAME

Obsolete. Provided for compatibility with much older Ferret versions.

LOAD/PERMANENT

Data loaded with LOAD/PERMANENT are kept in memory until a LOAD/TEMPORARY command is given that refers to the same data. See command LOAD/TEMPORARY (below). Note that this command may cause memory fragmentation. It should generally be given immediately following CANCEL MEMORY and preferably is used only to load file variables (as opposed to expressions).

Note that redefining or canceling any user-defined variables will cause all memory loaded from to user-defined variables to be cleared, including data loaded with LOAD/PERMANENT. Memory loaded from file variables is not cleared.


LOAD/TEMPORARY (default)

Data loaded with LOAD or LOAD/TEMPORARY is brought into memory but may be unloaded based on a priority scheme of least recent use when memory space is required.