# The While Construct - HP 49g+ User Manual

Graphing calculator.

Store this program in a variable @@S3@@. Verify the following exercises: J
3 @@@S3@@
Result: S:14
5 @@@S3@@
Result: S:55
10 @@@S3@@
Result: S:385
30 @@@S3@@
Result: S:9455
Example 3 – generate a list using a DO...UNTIL...END construct
Type in the following program
→ xs xe dx
xe xs – dx / ABS 1. + xs → n x
«
«
'x+dx' EVAL DUP 'x' STO UNTIL 'x≥xe' END n →LIST " " "
and store it in variable @GLIS3.
Check out that the program call 0.5 ` 2.5 ` 0.5 ` @GLIS3
produces the list {0.5 1. 1.5 2. 2.5}.
To see step-by-step operation use the program DBUG for a short list, for
example:
J1 # 1.5 # 0.5 `
['] @GLIS3 `
„°LL @) @ RUN@ @@DBG@
Use @SST↓@ to step into the program and see the detailed operation of each
command.

## The WHILE construct

The general structure of this command is:
WHILE logical_statement REPEAT program_statements END
The WHILE statement will repeat the program_statements while
logical_statement is true (non zero). If not, program control is passed to
the statement right after END. The program_statements must include a
4 @@@S3@@ Result: S:30
8 @@@S3@@ Result: S:204
20 @@@S3@@ Result: S:2870
100 @@@S3@@ Result: S:338350
Enter parameters 1 1.5 0.5
Enter the program name in level 1
Start the debugger.
«
xs DO
Page 21-62