# pdesurf

Shorthand command for surface plot

This page describes the legacy workflow. Use it when you work with legacy code and do not plan to convert it to use the recommended approach. Otherwise, use `pdeplot`.

## Syntax

```pdesurf(p,t,u) ```

## Description

`pdesurf(p,t,u)` plots a 3-D surface of PDE node or triangle data. If `u` is a column vector, node data is assumed, and continuous style and interpolated shading are used. If `u` is a row vector, triangle data is assumed, and discontinuous style and flat shading are used.

`h = pdesurf(p,t,u)` additionally returns handles to the drawn axes objects.

For node data, this command is just shorthand for the call

```pdeplot(p,[],t,'XYData',u,'XYStyle','interp',... 'ZData',u,'ZStyle','continuous',... 'ColorBar','off'); ```

and for triangle data it is

```pdeplot(p,[],t,'XYData',u,'XYStyle','flat',... 'ZData',u,'ZStyle','discontinuous',... 'ColorBar','off'); ```

If you want to have more control over your surface plot, use `pdeplot` instead of `pdesurf`.

## Examples

collapse all

Surface plot of the solution to the equation $-\Delta u=1$ over the geometry defined by the L-shaped membrane. Use Dirichlet boundary conditions $u=0$ on $\partial \Omega$.

```[p,e,t] = initmesh('lshapeg'); [p,e,t] = refinemesh('lshapeg',p,e,t); u = assempde('lshapeb',p,e,t,1,0,1); pdesurf(p,t,u)```