wiki:ShDerive

Version 1 (modified by MarcusWalther, 15 years ago) (diff)

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compute derivative

command: DERIVE <trc-list> <algorithm>

Computes derivatives of all traces given by <trc-list>. The input traces remain unchanged. The DERIVE command creates new traces containing the derivatives.

parameters

  • <trc-list> parameter type: trace list
    List of traces to be derived. These traces remain unchanged.
  • <algorithm> parameter type: integer
    ID of algorithm used to compute derivative. Valid vales are 1 to 5. The algorithms are listed below (h is sample distance):
    1. y'[i] = 1/(2h) (-y[i-1] + y[i+1])
    2. y'[i] = 1/(12h) (y[i-2] - 8y[i-1] + 8y[i+1] - y[i+2])
    3. y'[i] = 1/h (-y[i] + y[i+1])
    4. y'[i] = 1/(2h) (-3y[i] + 4y[i+1] - y[i+2])
    5. y'[i] = 1/(12h) (-3y[i-1]-10y[i]+18y[i+1]-6y[i+2]+y[i+3])

qualifiers

  • /qual
    Explanation

example

derive 1-3 3
computes derivative of traces 1-3 by algorithm number 3