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# ezmeshc

Easy-to-use combination mesh/contour plotter

## Syntax

ezmeshc(fun)
ezmeshc(fun,domain)
ezmeshc(funx,funy,funz)
ezmeshc(funx,funy,funz,[smin,smax,tmin,tmax])
ezmeshc(funx,funy,funz,[min,max])
ezmeshc(...,n)
ezmeshc(...,'circ')
ezmesh(axes_handle,...)
h = ezmeshc(...)

## Description

ezmeshc(fun) creates a graph of fun(x,y) using the meshc function. fun is plotted over the default domain -2π < x < 2π, -2π < y < 2π.

fun can be a function handle or a string (see the Tips section).

ezmeshc(fun,domain) plots fun over the specified domain. domain can be either a 4-by-1 vector [xmin, xmax, ymin, ymax] or a 2-by-1 vector [min, max] (where min < x < max, min < y < max).

ezmeshc(funx,funy,funz) plots the parametric surface funx(s,t), funy(s,t), and funz(s,t) over the square: -2π < s < 2π, -2π < t < 2π.

ezmeshc(funx,funy,funz,[smin,smax,tmin,tmax]) or ezmeshc(funx,funy,funz,[min,max]) plots the parametric surface using the specified domain.

ezmeshc(...,n) plots fun over the default domain using an n-by-n grid. The default value for n is 60.

ezmeshc(...,'circ') plots fun over a disk centered on the domain.

ezmesh(axes_handle,...) plots into the axes with handle axes_handle instead of the current axes (gca).

h = ezmeshc(...) returns the handle to a surface object in h.

## Examples

Create a mesh/contour graph of the expression

over the domain -5 < x < 5, -2*pi < y < 2*pi:

```ezmeshc('y/(1 + x^2 + y^2)',[-5,5,-2*pi,2*pi])
view(-65.5,26)```

Use the mouse to rotate the axes to better observe the contour lines (this picture uses a view of azimuth = -65.5 and elevation = 26)

expand all

### Passing the Function as a String

Array multiplication, division, and exponentiation are always implied in the string expression you pass to ezmeshc. For example, the MATLAB® syntax for a mesh/contour plot of the expression

`sqrt(x.^2 + y.^2);`

is written as

`ezmeshc('sqrt(x^2 + y^2)')`

That is, x^2 is interpreted as x.^2 in the string you pass to ezmeshc.

If the function to be plotted is a function of the variables u and v (rather than x and y), then the domain endpoints umin, umax, vmin, and vmax are sorted alphabetically. Thus, ezmeshc('u^2 - v^3',[0,1],[3,6]) plots u2 - v3 over 0 < u < 1, 3 < v < 6.

### Passing a Function Handle

Function handle arguments must point to functions that use MATLAB syntax. For example, the following statements define an anonymous function and pass the function handle fh to ezmeshc.

```fh = @(x,y) sqrt(x.^2 + y.^2);
ezmeshc(fh)```

Note that when using function handles, you must use the array power, array multiplication, and array division operators (.^, .*, ./) since ezmeshc does not alter the syntax, as in the case with string inputs.

```function z = myfun(x,y,k)
`ezmeshc(@(x,y)myfun(x,y,2))`