HP 35s Scientific manual Program Control with I/J, Equations with I/J, Unnamed indirect variables

STO(I)/(J)	INPUT(I)/(J)
RCL(I)/(J)	VIEW(I)/(J)
STO +, –,⋅ ,⎟, (I)/(J)	DSE(I)/(J)
RCL +, –,⋅ ,⎟, (I)/(J)	ISG(I)/(J)
X<>(I)/(J)	SOLVE(I)/(J)
FN=(I)/(J)	∫ FN d(I)/(J)

You can not solve or integrate for unnamed variables or statistic registers.

Program Control with (I)/(J)

Since the contents of I can change each time a program runs — or even in different parts of the same program — a program instruction such as STO (I) or (J) can store value to a different variable at different times. For example, STO(-1) indicates storing the value in Variable A. This maintains flexibility by leaving open (until the program runs) exactly which variable or program label will be needed.

Indirect addressing is very useful for counting and controlling loops. The variable I or J serves as an index, holding the address of the variable that contains the loop– control number for the functions DSE and ISG.

Equations with (I)/(J)

You can use (I) or (J) in an equation to specify a variable indirectly. Notice that  or  means the variable specified by the number in variable I or J (an indirect reference), but that I or J and or  (where the user parenthesis are used instead of the (I) or (J) key) means variable I or J.

Unnamed indirect variables

Placing a positive number into variable I or J allows you to access up to 801 indirect variables. The following example indicates how to use them.

Programming Techniques 14-23