drawmag (Mu Analysis and Synthesis Toolbox)

Mu Analysis and Synthesis Toolbox

drawmag

Provide an interactive mouse-based log-log sketch and fitting tool

Syntax

```
[sysout,pts] = drawmag(in,init_pts)
```

Description
drawmag interactively uses the mouse in the plot window to create a VARYING matrix pts and a stable, minimum-phase SYSTEM sysout, which approximately fits, in magnitude, the frequency VARYING matrix in pts.

Input arguments:

in
either a VARYING matrix which is plotted each time as a reference or a CONSTANT matrix of the form [x_min x_max y_min y_max] specifying the plot window on the data.

init_pts
optional VARYING matrix of initial set of points

in	either a VARYING matrix which is plotted each time as a reference or a CONSTANT matrix of the form [x_min x_max y_min y_max] specifying the plot window on the data.
`init_pts`	optional VARYING matrix of initial set of points

Output arguments

sysout
SYSTEM matrix fitting pts.

pts
VARYING matrix of points.

:

`sysout`	SYSTEM matrix fitting `pts`.
`pts`	VARYING matrix of points.

While drawmag is running, all interaction with the program is through the mouse and/or the keyboard. The mouse, if there is one, must be in the plot window. The program recognizes several commands:

Clicking the mouse button adds a point at the crosshairs. If the crosshairs are outside the plotting window, the points will be plotted when the fitting, windowing, or replotting modes are invoked. Typing a is the same as clicking the mouse button.
Typing r removes the point with frequency nearest that of the crosshairs.
Typing any integer between 0-9 fits the existing points with a transfer function of that order. The fitting routine approximately minimizes the maximum error in a log sense. The new fit is displayed along with the points, and the most recent previous fit, if it exists.
Typing w uses the crosshair location as the initial point in creating a window. Moving the crosshairs and clicking the mouse or pressing any key then gives a second point at the new crosshair location. These two points define a new window on the data, which is immediately replotted. This is useful in fine tuning parts of the data. Windowing may be called repeatedly.
Typing p simply replots the data using a window that covers all the current data points as well as whatever was specified in in. Typically used after windowing to view all the data.
Typing k invokes the keyboard using the keyboard command. Caution should be exercised when using this option, as it can wreak havoc on the program if variables are changed.

See Also
axis, ginput, magfitlp, musynfit, vplot

dkitgui dypert, sisorat