Program code with solve function

[Gene222]

Thank you for your explanation. I corrected some of the older posts.

(06-29-2024 02:28 AM)ftneek Wrote:  

(06-28-2024 05:54 PM)Gene222 Wrote:  2. In the program below, the variable noX is a purge variable that "does not exist". Is the variable noX just a symbolic variable within the confines of the solve function?

The first argument of the solve command is Expr, an expression in any variable. By default solve solves tries to isolate x so if your expression has an x it can be omitted. If your expression does not have an x and the second argument is omitted, then no solution is provided (it solves for Var=x by default). Most of that can be inferred by reading the help text for the solve() command, though it doesn't seem to explicitly state the default is x.

In CAS, any variable that has not been assigned a value is 'symbolic'.
purge(x)
type(x) -> DOM_IDENT
x:=1
type(x) -> DOM_INT

Also gX:='gX' shouldn't really do anything. In CAS View:
purge(x)
x:='x' -> "No such variable x"