func-plot

A small Rust function plotter. Each expression is drawn in a different color on shared axes.

Start the program, then enter one expression per line in the same terminal. The first valid expression opens the plot window; later expressions are added to it immediately.

cargo run
f(x)> sin(x)
f(x)> cos(x)
f(x)> -x^2/10

Type :quit in the terminal or close the window to exit. Invalid expressions are reported without removing curves already on the plot.

The range is min;max;step and defaults to -10;10;0.02. Set it at startup if needed:

cargo run -- --range "-5;5;0.01"

You can also pass initial expressions as arguments, then keep adding expressions in the terminal:

cargo run -- "x^2" "-x+2" --range "-5;5;0.01"

Quote expressions passed as arguments so the shell does not interpret operators or parentheses. Supported operators are +, -, *, /, and ^; signs can be unary, as in -x^2 or 2^-3. Power binds more tightly than unary minus, so -x^2 means -(x^2). Functions are sin(...), cos(...), sqrt(...), and log(...) (natural logarithm). Constants are pi and e. Multiplication must be explicit: use 2*x, not 2x.

The plot skips undefined values and breaks lines across large jumps.