smooth
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Apply a smoothing to the vector x.
- Usage
smooth(x {, type=0 {, m=1 {, s=1}}})
- x
- data vector
- m
- smoothing length; 0 < m <=
nrow(x)/2
(default=1) - type
- selects the smoothing algorithm (default=0)
- soutput step size; 0 < s <=
nrow(x)/2
(default=1)
- Description
The smoothing function is selected by the argument type. The smoothed value xs[i] is computed from the data values x[i-m] to x[i+m]. The general form of the smoothing function is:
type | smoothing algorithm | xs[i] = |
---|---|---|
0 | average | (x[i-m]+x[i-m+1]+..+x[i]+..+x[i+m-1]+ x[i+m]) / (2*m+1) |
0 | average with reciprocal weights | (x[i-m]/(m+1)x[i-m+1]/m+..+x[i]+..+x[i+m-1]/m+ x[i+m]/(m+1)) / (1 + 2*m+1) |
- Result
- A vector r with
nrow(x)/s
elements. The value r[j] is set to the value xs[j*s] of the smoothed data vector.