HP (Hewlett-Packard) 50g ユーザーズマニュアル

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Example – generate a list of numbers using a FOR…STEP construct
Type in the program:
«
→ xs xe dx 
«
 xe xs – dx / ABS 1. + 
→ n 
«
 xs xe FOR x x 
dx STEP n 
→LIST » » »
and store it in variable 
@GLIS2.
Θ Check out that the program call  0.5 ` 2.5 ` 0.5 ` @GLIS2
produces the list {0.5 1. 1.5 2. 2.5}.
Θ To see step-by-step operation use the program  DBUG for a short list, for
example: 
J
1 # 1.5 # 0.5 `
Enter parameters 1  1.5  0.5
[‘]
  @GLIS2  `
Enter the program name in level 1
„°LL
@)@RUN@   @@DBG@
Start the debugger.  
Use
@SST↓@ to step into the program and see the detailed operation of each 
command.
The DO construct
The general structure of this command is:
DO program_statements UNTIL logical_statement END
The DO command starts an indefinite loop executing the program_statements 
until the logical_statement returns FALSE (0). The logical_statement must 
contain the value of an index whose value is changed in the 
program_statements
.
Example 1 - This program produces a counter in the upper left corner of the 
screen that adds 1 in an indefinite loop until a keystroke (press any key) stops 
the counter:  
«
 0 DO DUP 1 DISP 1 + UNTIL KEY END DROP 
»
Command KEY evaluates to TRUE when a keystroke occurs.
Example 2 – calculate the summation S using a DO…UNTIL…END construct