HP 113394 User Guide - Page 130

130 Section 9: Branching and Looping These rules can be summarized as "DO if TRUE". The program line immediately following that containing the conditional test instruction can contain any instruction; however, the most commonly used instruction there is i. If a i instruction follows a conditional test instruction, program execution branches elsewhere in program memory if the condition is true and continues with the next line in program memory if the condition is false. Example: The following program calculates income tax at a rate of 20% on incomes of $20,000 or less and 25% on incomes of more than $20,000. To conserve program lines, the program assumes that the test value - 20,000 - has been stored in register R0 and the tax rates - 20 and 25 - have been stored in registers R1 and R2, respectively. Note: If a program requires that certain numbers be in the X- and Y-registers when instructions such as go are executed, it is extremely helpful when writing the program to show the quantities in each register after each instruction is executed, as in the following diagram (which shows an RPN mode program, although it works in a similar way in ALG mode.). File name: hp 12c pt_user's guide_English_HDPMF123E27 Page: 130 of 275 Printed Date: 2005/8/1 Dimension: 14.8 cm x 21 cm