Texas Instruments TI-83 Plus Manual page 51

Chapter 2: TI-83 Plus Specific Information
Note: These inputs are output from a successful Symbol Table search, such as FindSym.
DelVar
DelVarArc
DelVarNoArc
Note: OP1 through OP6 are kept intact.
For example, if matrix [A] exists and is not archived, delete it and recreate it with a
dimension of five rows and three columns.
return CA = 0 if successful, or
CA = 1 if it was archived or there was not enough free RAM to create it.
TI-83 Plus Developer Guide
Error if the variable is archived. This routine checks the contents of
the b register to be non-zero. If the contents is non-zero, it
assumes the variable is archived and generates a system error.
Otherwise, delete it from RAM. The b register is set by any of the
Symbol Table search routines to reflect whether or not a variable is
archived.
Delete the variable if archived or unarchived. This routine checks
the contents of the b register to be non-zero. If the content is non-
zero, then it assumes the variable is archived and deletes it from
the archive. Otherwise, it deletes it from RAM. The b register is set
by any of the Symbol Table search routines to reflect whether or
not a variable is archived.
Assumes the variable is not archived and deletes it from RAM.
This routine does not check the contents of the b register and
assumes the pointers input are RAM pointers, not pointers into the
archive space. Only use this routine if you are absolutely sure that
the variable resides in RAM.
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Third Release May 28, 2002