ARRDELETE Name
ARRDELETE
Author
Craig B. Markwardt, NASA/GSFC Code 662, Greenbelt, MD 20770
craigm@lheamail.gsfc.nasa.gov Purpose
Remove a portion of an existing array.
Calling Sequence
NEWARR = ARRDELETE(INIT, [AT=POSITION,] [LENGTH=NELEM])
Description
ARRDELETE will remove or excise a portion of an existing array,
INIT, and return it as NEWARR. The returned array will never be
larger than the initial array.
By using the keywords AT and LENGTH, which describe the position
and number of elements to be excised respectively, any segment of
interest can be removed. By default the first element is removed.
Inputs
INIT - the initial array, which will have a portion deleted. Any
data type, including structures, is allowed. Regardless of
the dimensions of INIT, it is treated as a one-dimensional
array. If OVERWRITE is not set, then INIT itself is
unmodified.
Keywords
AT - a long integer indicating the position of the sub-array to be
deleted. If AT is non-negative, then the deleted portion
will be NEWARR[AT:AT+LENGTH-1]. If AT is negative, then it
represents an index counting from then *end* of INIT,
starting at -1L.
Default: 0L (deletion begins with first element).
LENGTH - a long integer indicating the number of elements to be
removed.
OVERWRITE - if set, then INIT will be overwritten in the process of
generating the new array. Upon return, INIT will be
undefined.
COUNT - upon return, the number of elements in the resulting array.
If all of INIT would have been deleted, then -1L is
returned and COUNT is set to zero.
EMPTY1 - if set, then INIT is assumed to be empty (i.e., to have
zero elements). The actual value passed as INIT is
ignored.
Returns
The new array, which is always one-dimensional. If COUNT is zero,
then the scalar -1L is returned.
See Also
STORE_ARRAY in IDL Astronomy Library
Modification History
Written, CM, 02 Mar 2000
Added OVERWRITE and EMPTY1 keyword, CM 04 Mar 2000