Jul 2, 2018 · Feb 24, 2018 · Feb 24, 2018 · Jul 2, 2018
diff --git a/control/margins.py b/control/margins.py
            Linear SISO system
        mag, phase, omega : sequence of array_like
            Arrays of magnitudes (absolute values, not dB), phases (degrees),
            and corresponding frequencies.Crossover frequencies returned are
            and corresponding frequencies. Crossover frequencies returned are
            in the same units as those in `omega` (e.g., rad/sec or Hz).
    returnall: bool, optional
        If true, return all margins found. Iffalse (default), return only the
        minimum stability margins.For frequency data or FRD systems, only one
 margin is found and returned.
        If true, return all margins found. IfFalse (default), return only the
        minimum stability margins. For frequency data or FRD systems, only
 margins in the given frequency region can be found and returned.
    epsw: float, optional
        Frequencies below this value (default 0.0) are considered static gain,
        and not returned as margin.
    sm: float or array_like
        Stability margin, the minimum distance from the Nyquist plot to -1
    wg: float or array_like
 Gain margin crossover frequency (where phasecrosses -180 degrees)
 Frequency for gain margin (at phasecrossover, phase = -180 degrees)
    wp: float or array_like
 Phase margin crossover frequency (where gaincrosses 0 dB)
 Frequency for phase margin (at gaincrossover, gain = 0 dB)
    ws: float or array_like
 Stability margin frequency (where Nyquist plot is closest to -1)
 Frequency for stability margin (complex gain closest to -1)
    """

    try:
        Gain margin
    pm : float
        Phase margin (in degrees)
 Wcg: float
 Gain crossover frequency (corresponding tophasemargin)
 Wcp: float
 Phase crossover frequency (corresponding togainmargin) (in rad/sec)
 wg: float
 Frequency for gain margin (at phase crossover,phase= -180 degrees)
 wp: float
 Frequency for phase margin (at gain crossover,gain= 0 dB)

    Margins are of SISO open-loop. If more than one crossover frequency is
    detected, returns the lowest corresponding margin.
    Margins are calculated for a SISO open-loop system.

    If there is more than one gain crossover, the one at the smallest
    margin (deviation from gain=0dB), in absolute sense, is
    returned. Likewise the smallest phase margin (in absolute sense)
    is returned.

    Examples
    --------
    >>> sys = tf(1, [1, 2, 1, 0])
    >>> gm, pm,Wcg, Wcp = margin(sys)
    >>> gm, pm,wg, wp = margin(sys)

    """
    if len(args) == 1:
Original file line number	Diff line number	Diff line change
Expand Up		@@ -108,12 +108,12 @@ def stability_margins(sysdata, returnall=False, epsw=0.0):
		Linear SISO system
		mag, phase, omega : sequence of array_like
		Arrays of magnitudes (absolute values, not dB), phases (degrees),
		and corresponding frequencies.Crossover frequencies returned are
		and corresponding frequencies. Crossover frequencies returned are
		in the same units as those in `omega` (e.g., rad/sec or Hz).
		returnall: bool, optional
		If true, return all margins found. Iffalse (default), return only the
		minimum stability margins.For frequency data or FRD systems, only one
		margin is found and returned.
		If true, return all margins found. IfFalse (default), return only the
		minimum stability margins. For frequency data or FRD systems, only
		margins in the given frequency region can be found and returned.
		epsw: float, optional
		Frequencies below this value (default 0.0) are considered static gain,
		and not returned as margin.
Expand All		@@ -127,11 +127,11 @@ def stability_margins(sysdata, returnall=False, epsw=0.0):
		sm: float or array_like
		Stability margin, the minimum distance from the Nyquist plot to -1
		wg: float or array_like
		Gain margin crossover frequency (where phasecrosses -180 degrees)
		Frequency for gain margin (at phasecrossover, phase = -180 degrees)
		wp: float or array_like
		Phase margin crossover frequency (where gaincrosses 0 dB)
		Frequency for phase margin (at gaincrossover, gain = 0 dB)
		ws: float or array_like
		Stability margin frequency (where Nyquist plot is closest to -1)
		Frequency for stability margin (complex gain closest to -1)
		"""

		try:
Expand DownExpand Up		@@ -340,18 +340,22 @@ def margin(*args):
		Gain margin
		pm : float
		Phase margin (in degrees)
		Wcg: float
		Gain crossover frequency (corresponding tophasemargin)
		Wcp: float
		Phase crossover frequency (corresponding togainmargin) (in rad/sec)
		wg: float
		Frequency for gain margin (at phase crossover,phase= -180 degrees)
		wp: float
		Frequency for phase margin (at gain crossover,gain= 0 dB)

		Margins are of SISO open-loop. If more than one crossover frequency is
		detected, returns the lowest corresponding margin.
		Margins are calculated for a SISO open-loop system.

		If there is more than one gain crossover, the one at the smallest
		margin (deviation from gain=0dB), in absolute sense, is
		returned. Likewise the smallest phase margin (in absolute sense)
		is returned.

		Examples
		--------
		>>> sys = tf(1, [1, 2, 1, 0])
		>>> gm, pm,Wcg, Wcp = margin(sys)
		>>> gm, pm,wg, wp = margin(sys)

		"""
		if len(args) == 1:
Expand Down