bodeplot

LaTeX package to plot Bode, Nichols, and Nyquist diagrams. Inspired by the bodegraph package.

Author: Rushikesh Kamalapurkar ([email protected])

License: LPPL-1.3c

Limitations

1 Before version 1.2, in pgf mode, the package set trig format plots to rad globally. Version 1.2 onwards, this option is passed to each addplot command individually so it does not affect non-bodeplot plots. To roll back to pre-v1.2 behavior, load the package with \usepackage[pgf]{bodeplot}[=2024-02-06]. 2. TF commands are wrapped between -180 and 180 degrees in pgf mode. 3. Version 1.0.8 and newer store gnuplot temporary files in the working directory. Use class option declutter to restore pre-v1.0.8 behavior. Option declutter can cause errors if used with a tikzexternalize prefix.

Compilation instructions

1. latex bodeplot.ins to generate bodeplot.sty
2. To compile documentation (needs gnuplot on system PATH):

pdflatex bodeplot.dtx --shell-escape
makeindex -s gind.ist bodeplot.idx
makeindex -s gglo.ist -o bodeplot.gls bodeplot.glo
pdflatex bodeplot.dtx --shell-escape
pdflatex bodeplot.dtx --shell-escape

Added functionality over bodegraph

• New \BodeZPK and \BodeTF commands to generate Bode plots of any transfer function given either poles, zeros, gain, and delay, or numerator and denominator coefficients and delay
• All plots are fully customizable using pgf options (see package documentation for a full list of commands, environments, and options)
• Support for unstable poles and zeros.
• Support for complex poles and zeros.
• Support for general stable and unstable second order transfer functions.
• Support for both gnuplot (default) and pgfplots (package option pgf).
• Support for rad/s (default) and Hz (package option Hz or pgf key frequency unit=Hz for per-plot change) frequency units.
• Support for deg (default) and rad (package option rad or pgf key phase unit=rad for per-plot change) phase units.
• Support for linear and asymptotic approximation of magnitude and phase plots of any transfer function given poles, zeros, and gain.

Basic Bode/Nyquist/Nichols commands

See package documentation for a full list of commands, environments, and options.

• Given Zeros, Poles, Gain, and Delay (asymptotic and linear approximation available for systems without delay):

\BodeZPK % (OR \NicholsZPK[samples=1000] OR NyquistZPK[samples=1000])
{% 
  z/{0,{-0.1,-0.5},{-0.1,0.5}}, % zeros at s = 0, s = -0.1 - 0.5j, and s = -0.1 + 0.5j
  p/{{-0.5,-10},{-0.5,10}}, % poles at s = -0.5 - 10j, and s = -0.5 + 10j
  k/10, % gain
  d/0.01, % delay
}
{0.01} % frequency range start
{100} % frequency range end

• Given Numerator and denominator coefficients and delay (does not support approximation):

\BodeTF % (OR \NicholsTF[samples=1000] OR NyquistTF[samples=1000])
{%
  num/{10,2,2.6,0}, % numerator coefficients
  den/{1,1,100.25}, % denominator coefficients
  d/0.01, % delay
}
{0.001} % frequency range start
{100} % frequency range end