NAME
fplot – plot elementary function

SYNOPSYS
fplot [ –c [ –s size ]] [ –r range ] functions ...

DESCRIPTION
Fplot plots elementary functions separated by spaces. The default output is the screen, but if the –c option is specified, the plot is written to the standard output as an r8g8b8 image(6). The latter image size is either 640x480 or the one specified by the –s option's argument (in the WIDTHxHEIGHT format). The –r option accepts as argument the x and y ranges, in the format xmin:xmax ymin:ymax.

Each function to be plotted may be a combination of the independent variable x, the elementary operations (+, –, *, / and %), and the functions described in sin(2) and exp(2). The exception being that x^n raises x to the nth power, log is the base 10 logarithm, and ln is the natural logarithm.

EXAMPLES
Plot the absolute value and x^3 functions to a 400x400 image(6) on standard output and view with page(1).
fplot –c –s 400x400 'sqrt(x*x)' 'x^3' | page

SOURCE
/sys/src/cmd/fplot.c

SEE ALSO
exp(2), sin(2), image(6), plot(1).

DIAGNOSTICS
Fplot either exits with syntax error or an empty status.

BUGS
Parentheses after unary operators are not special, e.g. sin(x)/2 is parsed as sin x/2 = sin(x/2) and not (sin x)/2.

There is no unary plus or minus.

HISTORY
Fplot first appeared in 9front (July, 2011).