MATLAB Function Reference |
Plot a function between specified limits
Syntax
fplot(fun,limits) fplot(fun,limits,LineSpec) fplot(fun,limits,tol) fplot(fun,limits,tol,LineSpec) fplot(fun,limits,n) fplot(axes_handle,...) [X,Y] = fplot(fun,limits,...)
Description
fplot
plots a function between specified limits. The function must be of the form y = f(x), where x is a vector whose range specifies the limits, and y
is a vector the same size as x
and contains the function's value at the points in x (see the first example). If the function returns more than one value for a given x, then y is a matrix whose columns contain each component of f(x) (see the second example).
fplot(fun,limits)
plots fun
between the limits specified by limits
. limits
is a vector specifying the x-axis limits ([xmin
xmax])
, or the x- and y-axes limits, ([xmin
xmax
ymin
ymax]
).
x
that may be passed to eval
, such as 'sin(x)'
, 'diric(x,10)'
, or '[sin(x),cos(x)]'
The function f(x) must return a row vector for each element of vector x. For example, if f(x) returns [f1(x),f2(x),f3(x)]
then for input [x1;x2]
the function should return the matrix
fplot(
plots fun
,limits,LineSpec
)
fun
using the line specification LineSpec
.
fplot(fun,limits,tol)
plots fun
using the relative error tolerance tol
(the default is 2e-3
, i.e., 0.2 percent accuracy).
fplot(fun,limits,tol,
plots LineSpec
)
fun
using the relative error tolerance tol
and a line specification that determines line type, marker symbol, and color. See LineSpec
for more information.
fplot(fun,limits,n)
with n >= 1
plots the function with a minimum of n+1
points. The default n
is 1
. The maximum step size is restricted to be (1/n)*(xmax-xmin)
.
fplot(fun,lims,...)
accepts combinations of the optional arguments tol
, n
, and LineSpec
, in any order.
fplot(axes_handle,...)
plots into the axes with handle axes_handle
instead of the current axes (gca
).
[X,Y] = fplot(fun,limits,...)
returns the abscissas and ordinates for fun
in X
and Y
. No plot is drawn on the screen; however, you can plot the function using plot(X,Y)
.
Remarks
fplot
uses adaptive step control to produce a representative graph, concentrating its evaluation in regions where the function's rate of change is the greatest.
Examples
Plot the hyperbolic tangent function from -2 to 2:
Create an M-file, myfun
, that returns a two-column matrix:
Create a function handle pointing to myfun
:
Plot the function with the statement
Addition Examples
This example passes function handles to fplot
, one created from a MATLAB function and the other created from an anonymous function.
hmp = @humps; subplot(2,1,1);fplot(hmp,[0 1]) sn = @(x) sin(1./x); subplot(2,1,2);fplot(sn,[.01 .1])
See Also
eval
, ezplot
, feval
, LineSpec
, plot
Function Plots for related functions
Plotting Mathematical Functions for more examples
format | fprintf |
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