def plcfreq(self, spec="", sectbeg="", sectend="", **kwargs):
    """Plots the frequency response for the given CYCSPEC specification.

    APDL Command: PLCFREQ

    Parameters
    ----------
    spec
        CYCSPEC specification number (ordered 1 to N in the order input;
        use CYCSPEC,LIST to view the current list order). Defaults to 1.

    sectbeg
        Beginning sector number to plot. Defaults to 1.

    sectend
        Ending sector number to plot. Defaults to the total number of
        sectors expanded (/CYCEXPAND).

    Notes
    -----
    Following a cyclic mode-superposition harmonic analysis, this command
    plots the result item given by a CYCSPEC specification versus the
    harmonic frequency, one curve for each of the specified sectors. A
    CYCCALC command must have been issued prior to this command.
    """
    command = f"PLCFREQ,{spec},{sectbeg},{sectend}"
    return self.run(command, **kwargs)