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Click Transform > Differentiated variables in the menu.
Enter a name for the new variable set.
Enter prefix, default: DIFF_
Enter Step duration. For more information, see Step duration.
Select Input variables or variable set.
Select Differential method. For more information, see Newton, Symmetric and High order.
1. The derivative options are:
  1. Newton: difference quotient (order 1)
  2. Symmetric: difference quotient (order 2)
  3. High order: five-point stencil
Select the Direction, Left or Right. See below that it is the formula used to derive the variable with the Newton method.
Click Save.

Info

title	Differentiated Methods

Formula used to derive the variable:

Newton: f'(x) = [f(x + 1 )-f(x)]/Step or f'(x) = [f(x)-f(x - 1)]/Step
Symmetric: f'(x) = [f(x + 1) - f(x - 1)] / [2 * Step]
High order: f'(x) = [-f(x + 2) + 8f(x + 1) - 8f(x - 1) + f(x - 2)] / [12 * Step]

With:

x: the index of the row
f(x): the value of the variable for row x
f'(x): the value of the derivative for row x
Step: Value defined by the field Step duration. It is the duration between two rows of the dataset. If Step duration is missing, the default value is 1.

Info

title	Direction

Formula used to derive the variable with the Newton method:

With :

x: the index of the row
f(x): the value of the variable for row x
f'(x): the value of the variable the derivative for row x
Step: Value defined by the field Step duration. It is the duration between two rows of the dataset. If Step duration is missing, the default value is 1.

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