This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.
 BUILT-IN MATHEMATICA SYMBOL

# NyquistGridLines

 NyquistGridLines is an option to NyquistPlot that specifies contours of constant magnitude and phase of a closed-loop system.
• The following settings can be given:
 None no contours drawn Automatic contours chosen automatically {magnitude,phase} contours specified by magnitude and phase are drawn
• magnitude values are the absolute values.
• phase values are given in radians.
• The following settings can be given for magnitude and phase:
 None no contours drawn Automatic contours chosen automatically {c1,c2,...} draw the contours {{c1,style1,r1},...} contours with specified styles and regions
• The default setting for is Dashed for magnitude contours and Dotted for phase contours.
• The setting specifies that a point should be included if yields True.
• The default value of is True.
Show the closed-loop magnitude and phase contours:
Show the closed-loop magnitude and phase contours:
 Out[1]=
 Scope   (9)
Choose contours automatically:
Show the specified magnitude and phase contours:
Use different contour styles:
Specify different regions:
Specify contours with magnitude -12 dB, -13 dB, -15 dB, and -18 dB:
Specify contours with phase from -60 to 60 degrees in increments of 10:
The contours depend on the feedback type:
The contours are shown only in the finite regions:
A discrete-time system:
 Applications   (1)
Estimate closed-loop magnitude and phase values at various frequencies:
New in 8