Scilab Function

fcontour - level curves on a 3D surface defined by a function

### Sequence d'appel

  `fcontour(xr,yr,f,nz,[theta,alpha,leg,flag,ebox,zlev])`
  `fcontour(xr,yr,f,nz,<opt_args>)`

### Parametres

- `xr,yr` : two real row vectors of size n1 and n2.
- `f` : is an external which defines the surface `z=f(x,y)`. It is first computed on the grid specified by `xr,yr`. Then, control is passed to the routine `contour`.
- `nz,` : see `contour`.
- `theta,alpha,leg,flag,ebox,zlev` : see `contour`.
- `<opt_args>` : see `contour`.

### Description

Draws level curves of a surface `z=f(x,y)`. The level curves are drawn on a 3D surface. The surface is given by the external function `f`. See `contour`.

The optional arguments `theta,alpha,leg ,flag,ebox, zlev`, can be passed by a sequence of statements `key1=value1, key2=value2`,

`flag`,`ebox`,`zlev`. In this case, the order has no special meaning.

You can change the format of the floating point number printed on the levels by using `xset("fpf",string)` where `string` gives the format in C format syntax (for example `string="%.3f"`). Use `string=""` to switch back to default format and Use `string=" "` to suppress printing.

Enter the command `fcontour()` to see a demo.

### Exemples

    deff("[z]=surf(x,y)","z=sin(x)*cos(y)");
    t=%pi*[-10:10]/10;

    fcontour(t,t,surf,10)

    xbasc();fcontour(t,t,surf,10,ebox=[-4 4 -4 4 -1 1],zlev=-1,flag=[0 1 4])

### Voir aussi

`contour` `contour2d` `fcontour2d`

### Auteur

J.Ph.C.