POLARGRID

Purpose:

Draws a polar grid on an XY plot.

Syntax:

POLARGRID(rmax, dtheta, dr, color, lstyle, rmin, rtheta, roff)

rmax

-

Optional. A real, the maximum radius of the polar grid. Defaults to -1, automatic.

dtheta

-

Optional. A real, the angle in degrees between polar grids lines. Defaults to 30 degrees.

dr

-

Optional. A real, the tic spacing along the labeled radial grid. Defaults to -1, automatic.

color

-

Optional. An integer, the grid color. Defaults to light grey (LGREY).

lstyle

-

Optional. An integer, the grid line style. Defaults to 2, dotted.

rmin

-

Optional. A real, the minimum radius of the polar grid. Defaults to -1, automatic.

rtheta

-

Optional. A real, the angle of the labeled radial grid in degrees. Defaults to 0 degrees (i.e. horizontal).

roff

-

Optional. A real, the offset of the first tic mark on the labeled radial grid. Defaults to 0.

 

Returns:

Nothing, a polar grid is drawn in the current window.

Example:

W1: 2*pi*((1..500)/500)

W2: 4 * sin(3 * W1)

W3: xy(w2*cos(w1), w2*sin(w1));setx(-6, 6);sety(-6, 6);setaspect(1);polargrid(4, 20, 0.5)

 

Creates an XY polar plot in W3. The polar grid has a radius of 4, the angle increment is 20 degrees and the radius increment is 0.5. The grid is drawn in light grey and is solid.

Example:

W4: xy(w2*cos(w1), w2*sin(w1));setx(-6, 6);sety(-6, 6);setaspect(1);polargrid(4, 10, 0.5, BLACK, 2, 0.0, 50.0, 2.0)

 

Same as above except the grid is drawn in dotted black, the labeled radial axis is drawn at 50 degrees and the first radial tic is 2.0.

Remarks:

POLARGRID is called by XYPOLARPLOT to produce a polar plot with polar grids.

 

See XYPOLARPLOT to generate a polar plot with grids given polar data (theta and r).

 

A value of -1 for any optional argument specifies the default value.

See Also:

LINEDRAW

XY

XYPOLARPLOT