HP 39gs - Manual (Page 240)

18-18 Programming
Example
1 A :
IF A==1
THEN MSGBOX " A EQUALS 1" :
END:
IF... THEN... ELSE...
END Executes the true-clause sequence of commands if the test-
clause is true, or the false-clause sequence of commands
if the test-clause is false.
IF test-clause
THEN true-clause ELSE false-clause END
Example
1 A :
IF A==1 THEN
MSGBOX "A EQUALS 1" :
ELSE
MSGBOX "A IS NOT EQUAL TO 1" :
END:
CASE...END Executes a series of test-clause commands that execute
the appropriate true-clause sequence of commands. Its
syntax is:
CASE
IF test-clause
1
THEN true-clause
1
END
IF test-clause
2
THEN true-clause
2
END
.
.
.
IF test-clause
n
THEN true-clause
n
END
END:
When CASE is executed, test-clause
1
is evaluated. If the
test is true, true-clause
1
is executed, and execution skips
to END. If test-clause
1
if false, execution proceeds to test-
clause
2
. Execution with the CASE structure continues until
a true-clause is executed (or until all the test-clauses
evaluate to false).
IFERR...
THEN...
ELSE…
END... Many conditions are automatically recognized by the HP
39gs as error conditions and are automatically treated as
errors in programs.
HP 39gs English.book Page 18 Wednesday, December 7, 2005 11:24 PM