president:  pvoc data surfing with pitch deviation
president   [flags] < floatsams > floatsams
        N:      fft length [1024]
        R:      sampling rate [44100]
        M:      window size in samples [4096]
        I:      interpolation factor in samples [512]
        f:      lookup control function [func]
        p:      pitch control function [pfunc]
        i:      duration of input [undefined]
        o:      duration of output [undefined]
        O:      time offset for function [0.]
        s:      floor for rescaling control function
        S:      ceiling for rescaling control function
        g:      multiplier for amplitude threshold[.001]


President is a variant of resident. Therefore,
you should know about resident (and pvanal) before
expecting to get president to obey your orders.
The added feature here is a separate function
for controlling instantaneous pitch transposition.
That means that president, unlike resident, uses
oscillator bank resynthesis. 
President considerately protects you from your
own frequency excesses by omitting frequencies
which rise about the Nyquist. Those of you
who don't practice safe spectra can remove
that feature yourself.