HP 95LX - Page 55

Rules and Limitations on Solver Equations
1. Equation names can contain up to 38 characters (including spaces)—although
only the first 12 characters will show up in the Solve Catalog.
2. A single equation cannot exceed 2279 characters (that’s five completely full 12-
line screens). A single equation can have up to 256 different variables.
3. Variable names can be up 15 characters, but the following characters are
forbidden: space, +,—, %, 7," (, 2, {, >, = u,4,5,35, 1, { 3 [, 1 andl.
Also, variable names cannot begin with a numeral, nor can they be identical to
any Solver function or operator name (see page 150 for a complete list).
4. Variable names are case sensitive; function names are not.
5. Because only the first 4 to 6 characters in a variable name appear on the menu
when you use a Solver equation, don’t name two or more variables with names
that begin with the same 4 to 6 characters. Otherwise, you could be confused
when choosing selections from the menu.
6. Theorderin which the variables are mentioned in the equationis the order that
they will appear in the calculation template and in the menu.
7. Constants (numbers) cannot have digit separators (e.g. the comma in 345,692)
or other characters.
8. You can use spaces and line breaks (the (M) key is used to start a new line) to
display an equation in a way that makes it easier to understand. But you must
not put spaces or line breaks in the middle of variable names or function names.
9. You can add comments to an equation at any point in an equation. The
comment must begin and end with an exclamation point (!). It’s a good idea
to not insert them into the middle of a name or large function expression.
10. When in doubt, use parentheses. Of course, you must have the same number
of closing and opening parentheses.
11.If you use the same variable name in two or more Solver equations, the value
stored in that variable will be used in both equations. Sometimes this is a good
thing; at other times, it leads to confusion. However, if you use the same
variable name in a Solver equation as a variable in one of the built-in
calculation templates (TVM, Business Percentages, etc.), the values will not be
shared between them.
Using the Solver 55