## Control Ratio of Axis Lengths and Data Unit Lengths

You can control the relative lengths of the *x*-axis,
*y*-axis, and *z*-axis (plot box aspect ratio).
You also can control the relative lengths of one data unit along each axis (data aspect
ratio).

### Plot Box Aspect Ratio

The plot box aspect ratio is the relative lengths of the *x*-axis, *y*-axis, and *z*-axis. By default, the plot box aspect ratio is based on the size of the figure. You can change the aspect ratio using the `pbaspect`

function. Set the ratio as a three-element vector of positive values that represent the relative axis lengths.

For example, plot an elongated circle. Then set the plot box aspect ratio so that the x-axis is twice the length of the *y*-axis and *z*-axis (not shown).

```
t = linspace(0,2*pi);
plot(sin(t),2*cos(t))
grid on
pbaspect([2 1 1])
```

Show the axes in a 3-D view to see the *z*-axis.

view(3)

For square axes, use `[1 1 1]`

. This value is similar to using the `axis square`

command.

```
t = linspace(0,2*pi);
plot(sin(t),2*cos(t))
grid on
pbaspect([1 1 1])
```

### Data Aspect Ratio

The data aspect ratio is the relative length of the data units along the *x*-axis, *y*-axis, and *z*-axis. You can change the aspect ratio using the `daspect`

function. Set the ratio as a three-element vector of positive values that represent the relative lengths of data units along each axis.

For example, set the ratio so that the length from 0 to 1 along the *x*-axis is equal to the length from 0 to 0.5 along the *y*-axis and 0 to 2 along the *z*-axis (not shown).

```
t = linspace(0,2*pi);
plot(sin(t),2*cos(t))
grid on
daspect([1 0.5 2])
```

Show the axes in a 3-D view to see the *z*-axis.

view(3)

For equal data units in all directions, use `[1 1 1]`

. This value is similar to using the `axis equal`

command. One data unit in the *x *direction is the same length as one data unit in the *y* and *z* directions.

```
t = linspace(0,2*pi);
plot(sin(t),2*cos(t))
grid on
daspect([1 1 1])
```

### Revert Back to Default Ratios

Change the data aspect ratio. Then revert back to the default plot box and data aspect ratios using the `axis normal`

command.

t = linspace(0,2*pi); plot(sin(t),2*cos(t)) grid on daspect([1 1 1]) axis normal