Type: Command
Description: Displays a list of CAS operations. Selecting one with OK displays a description, related operations, an example of the operation, and the option to copy the example to the command line. More details are given in Appendix C and Appendix H of the User’s Guide. If level 1 of the stack contains a string, the list of CAS operations will be displayed beginning at this point.
Access: | Catalog, …µ, or tools IL |
|
See also: | HELP |
|
| CASE | Command |
|
Type: |
| |
Description: | CASE Conditional Structure Command: Starts CASE … END conditional structure. | |
| The CASE … END structure executes a series of cases (tests). The first test that returns a true | |
| result causes execution of the corresponding | |
| default clause can also be included: this clause executes if all tests evaluate to false. The CASE | |
| command is available in RPN programming only. You cannot use it in algebraic programming. | |
| The CASE … END structure has this syntax: | |
| CASE |
|
|
| |
|
| |
| . |
|
| . |
|
|
| |
|
| |
| END |
|
| When CASE executes, | |
| execution skips to END. If | |
| structure continues until a true clause is executed, or until all the test clauses evaluate to false. If | |
| the default clause is included, it executes if all test clauses evaluate to false. | |
Access: | !°BRCH CASE | ( °is the |
Input/Output:
Level 1/Argument 1 | Level 1/Item 1 |
|
|
CASE | → |
THEN | T/F → |
END | → |
END | → |
|
|
Example: The following program takes a numeric argument from the stack:
•if the argument is negative, it is added to itself
•if the argument is positive, it is negated
•if the argument is zero, the program aborts
« → X « CASE
'X>0' THEN X NEG END 'X<0' THEN X DUP + END 'X==0' THEN 0 DOERR END END » »
See also: END, IF, IFERR, THEN