HP 49g+, Руководство пользователя, Страница: 710 / 862

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ERRM
This function returns a character string representing the error message of the
most recent error. For example, in Approx mode, if you try
0Y$ @ERRM
,
you get the following string:
“Infinite Result”
ERR0
This function clears the last error number, so that, executing ERRN afterwards,
in Approx mode, will return # 0h. For example, if you try
0Y$ @ERR0 @ERRN
, you get # 0h. Also, if you try
0Y$ @ERR0 @ERRM
, you get the empty string “ “.
LASTARG
This function returns copies of the arguments of the command or function
executed most recently. For example, in RPN mode, if you use:
3/2`
, and then use function LASTARG (
@LASTA
), you will get the
values 3 and 2 listed in the stack. Another example, in RPN mode, is the
following:
5U`
. Using LASTARG after these entries produces a 5.
Sub-menu IFERR
The
@)IFERR
sub-menu provides the following functions:
These are the components of the IFERR … THEN … END construct or of the
IFERR … THEN … ELSE … END construct. Both logical constructs are used
for trapping errors during program execution. Within the
@)ERROR
sub-menu,
entering
„ @)IFERR
, or
‚ @)IFERR
, will place the IFERR structure components in
the stack, ready for the user to fill the missing terms, i.e.,
The general form of the two error-trapping constructs is as follows: