batch
Batch digital filter.
Syntax
batch(indep_vec, dep_vec, low, high, [extension])
Argument
 indep_vec
 The independent vector of the curve to be filtered.
 dep_vec
 The dependent vector of the curve to be filtered.
 low
 The low cutoff frequency (scalar expression).
 high
 The high cutoff frequency (scalar expression).
 [extension]
 The number of points to extend the curve by (scalar) (optional).
Example
Curve Math Vectors  Result 

x = c1.x

Given c1, a curve is created which is filtered through an ideal bandpass filter with low cutoff frequency 5 and high cutoff frequency 8. 
Comments
The batch filter filters all points on a curve at once, or in a "batch." A Fast Fourier Transform (FFT) is used to transform the data into the frequencydomain where it is filtered. An inverse IFFT is then used to transform the data back into the timedomain. The resultant vector is the original curve filtered through an ideal filter with low and high cutoff frequencies.
It is assumed that the data is evenly sampled.
indep_vec and dep_vec must have the same number of elements. Both low and high must be nonnegative.
To create a bandpass filter, specify a high cutoff frequency (f_{high}) that is greater than the low cutoff frequency (f_{low}).
To create a notch filter, specify a high cutoff frequency (f_{high}) that is less than the low cutoff frequency (f_{low}).
Highpass and lowpass filters are handled in the same manner as bandpass and notch filters. For a lowpass filter, the low cutoff frequency should be zero. For a highpass filter, the high cutoff frequency should be zero.
If the cutoff frequency is greater than half the sampling Nyquist frequency, the curve is not filtered.
If the optional extension argument is used, the vector is extended at the beginning and end by extension points before filtering. These points are not present in the result. Using this option usually provides better accuracy at the ends of the resultant curve.