In 2D plots, the variable to use is x, in 3D plots, use x and y.
Multiplication is denoted by *, and division by /.
Exponents are denoted by**, and all multiplication must be
explicit. That is, 3x would generate and error, you would want
to use 3*x.
For example, the polynomial 3x4 + 4x - 2/3 would be
the following in Gnuplot:
Gnuplot also has a number of predefined functions. These are called by
putting the arguments in parenthesis, i.e., sin(x). These include the
The following are other examples of functions. Make sure you
understand what functions are being described.
- The standard trig functions, sin, cos, and tan Note, to
use the constant pi can be referenced by just using pi.
- The inverse trig functions , asin, acos, and atan.
- The hyperbolic trig functions, sinh, cosh, and tanh.
- The exp and log function. exp raises e to the power of its
argument. For example, 4e2x would be
4*exp(2*x) in Gnuplot. log returns the natural log (base
e) of it's argument. This corresponds to ln in normal
- For information on other functions, type help functions
- (x**2 - 4)/(x +2)
- x**2 + y**2 - (x*y)**(2/3)
- log(exp(x)) (Hint, this simplifies to x)
- 3*x**2 + 6/(1*y**2)
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Last Modified: 10/29/96