Interpolates a series by a factor using FFT zero insertion.
FZINTERP(series, n)
series |
- |
An input series or array. |
n |
- |
A real, the interpolation factor, |
A series or array.
W1: gsin(64, 1/64, 3)
W2: fzinterp(W1, 4)
W1 contains 64 samples of a 3 Hz sine wave sampled at 64 Hz.
W2 produces a 253 point interpolated 3 Hz sine wave with a sample rate of 64 * 4 = 256 Hz.
W3: fzinterp(W1, 3.5)
produces a 221 point interpolated 3 Hz sinewave with a sample rate of 64 * 3.5 = 224 Hz.
FZINTERP is identical to ZINTERP except that the interpolation factor (i.e. the multiple of the original sampling rate) is specified instead of the new rate. Although the interpolation factor N is NOT required to be an integer, for an output length L, the relation:
N = L / length(s)
must hold, so the actual interpolation factor might differ from N. See ZINTERP for algorithm details.