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Plotting a Smith Chart
Syntax smith(gammacolor)
See Also polar

Description
A smith chart contains solid lines denoting constant real and imaginary part for the impedance (z) with labels corresponding to the value that is constant. Dashed lines are drawn denoting constant real and imaginary part for the admittance (y). These lines have the same values as the corresponding impedance lines but are not labeled. The lines are drawn in Gamma space where
     Gamma = (z - 1) / (z + 1)
     Gamma = (1 - y) / (1 + y)
and Gamma < 1. In addition, the unit circle is drawn and tick marks are included with a spacing of 10 degrees around the circle. These tick marks are not labeled.

The values specified by the complex matrix gamma are included in the plot. The character matrix color has row dimension equal to the column dimension of gamma and specifies the color used to plot each of the columns of gamma. Row number j of color corresponds to the column number j of gamma and each row of color must be a valid O-Matrix plotting color and

If n is the row dimension of gamma. The elements of each column are plotted with a symbol that depends on their index within the column as follows:
First Index Last Index Symbol
1 ... n / 5 triangle
n / 5 + 1 ... (2 * n) / 5 star
(2 * n) / 5 + 1 ... (3 * n) / 5 plus
(3 * n) / 5 + 1 ... (4 * n) / 5 diamond
(4 * n) / 5 + 1 ... (5 * n) / 5 cross
Example
     theta = 0. : .2 : 2 * pi
     r     = theta / (2 * pi)
     gamma = r % exp(1i0 * theta)
     color = "red"
     smith(gamma, color)
     
returns the following plot

Reference
The initial contents of viewport zero, in the current graphic window, are erased and it is the current viewport when the plot is completed. The current graphic text font is rest to its default value. The aspect ratio for the current graphic window is set to 1. If you change this your smith chart will not be "square".