fplot

Purpose

Plot the graph of a function.

Synopsis

fplot('function',limits)
fplot('fstring',limits)
fplot(...,'marker')
fplot(...,'marker',tol)
[x,y] = fplot(...)

Description

fplot('function',limits) plots the function specified by function between the limits specified by the limits vector. function can be any MATLAB function name, including the name of a user-created function. limits can be a two-element vector specifying the x-axis limits for the plot, or a four-element vector specifying both x- and y-axis limits, [xmin xmax ymin ymax].

fplot('fstring',limits) evaluates and plots fstring, a function string that includes a variable x, such as 'sin(x)' or 'diric(x,10)'.

fplot(...,'marker') specifies the marker type for the plot. By default, fplot uses only a solid line. Valid marker strings are '-+', '-x', '-o', and '-*'.

fplot(...,'marker',tol) specifies the relative error tolerance tol. By default, tol is 2e-3.

[x,y] = fplot(...) returns the abscissae and ordinates for the function in the column vectors x and y. No plot is drawn on the screen. The function can then be plotted with plot(x,y).

Examples

Plot the hyperbolic tangent function from -2 to 2.

fplot('tanh',[-2 2])
The function defined in the M-file

function y = myfun(x)
y(:,1) = 200*sin(x(:))./x(:);
y(:,2) = x(:).^2;
is graphed with the statement:

fplot('myfun',[-20 20])

See Also

feval, plot

(c) Copyright 1994 by The MathWorks, Inc.