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difforms[d] - exterior differentiation
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Calling Sequence
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d(expr)
d(expr, forms)
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Parameters
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expr
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expression or list of expressions
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forms
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(optional) list of 1-forms, i.e. wdegree=one
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Description
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The function d computes the exterior derivative of an expression. If the expression is a list, then d is applied to each element in the list.
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When d is called with an expression and a list of 1-forms, any name of type scalar in the expression will be expanded in these 1-forms. It is assumed that the 1-forms are independent. For each 1-form, a new scalar is created to be the component for that 1-form.
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The command with(difforms,d) allows the use of the abbreviated form of this command.
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Examples
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| (1) |
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| (2) |
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![d(f, [w1, w2, w3])](/support/helpjp/helpview.aspx?si=7186/file03718/math93.png)
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| (3) |
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![d(f, [d(x), d(y[1]), v[1]])](/support/helpjp/helpview.aspx?si=7186/file03718/math100.png)
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![fx*d(x)+fy[1]*d(y[1])+fv[1]*v[1]](/support/helpjp/helpview.aspx?si=7186/file03718/math103.png)
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| (5) |
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![d([x*y, y^2, w2])](/support/helpjp/helpview.aspx?si=7186/file03718/math114.png)
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![[y*d(x)+x*d(y), 2*y*d(y), d(w2)]](/support/helpjp/helpview.aspx?si=7186/file03718/math117.png)
| (6) |
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