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Plotting The Response Of A Continuous Filter
 Syntax `fcplot(`xmin`, `xmax`, `ymin`, `ymax`, `cutoff`, `num`, `den`)` See Also fdplot

Description
Plots the response of a continuous filter in the current viewport, where xmin is an integer, real, or double-precision scalar specifying the minimum value on the `x`-axis; xmax is an integer, real, or double-precision scalar specifying the maximum value on the `x`-axis; ymin is an integer, real, or double-precision scalar specifying the minimum value on the `y`-axis; ymax is an integer, real, or double-precision scalar specifying the maximum value on the `y`-axis; cutoff is an integer, real, or double-precision row vector denoting the cutoff frequencies; num is an integer, real, or double-precision column vector specifying the numerator polynomial for the filter; and den is an integer, real, or double-precision column vector specifying the denominator polynomial for the filter. The `x`- and `y`-axis are log-scaled, and xmin, xmax, ymin, and ymax must be powers of 10 (e.g., 1, 10, 100). ``` ```The response function plotted is ```      |        __      |2      | num[ \/-1 w ]  |      ------------------      |        __      |2      | den[ \/-1 w ]  | ```where `w` is between xmin and xmax.

Example
The following program plots a normalized 2 pole Butterworth filter. ``` clear # num   = 1. den   = {1., sqrt(2.), 1.} ymin   = 1e-3 ymax   = 1e2 xmin   = 1e-1 xmax   = 1e1 cutoff = 1. fcplot(xmin, xmax, ymin, ymax, cutoff, num, den) ```