DiffAlgField _ DiffAlgForm -- contraction of a differential form with respect to a vector field

Synopsis

Usage:
X _ w
Operator: _
Inputs:
- X, an object of class DiffAlgField, a vector field
- w, an object of class DiffAlgForm, a differential form
Outputs:
- an object of class DiffAlgForm, the contraction of w with respect to X

Description

Given a vector field X and a differential form w, this function returns the contraction of w with respect to X. The function can be called as X _ w or as w _ X.

In this example we compute the contraction between a simple differential form and a vector field.

i1 : w = newForm("dx_0 * dx_1")

o1 = dx dx
       0  1

o1 : DiffAlgForm

i2 : Y = newField("ax_0")

o2 = ax
       0

o2 : DiffAlgField

i3 : Y _ w

o3 = dx
       1

o3 : DiffAlgForm