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Calling Sequence
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VectorField(v, c)
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Parameters
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v
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list or Vector; components specifying the coefficients of the basis vectors at each point in space
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c
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(optional) symbol[name, name, ...]; specify the coordinate system and coordinate names of the vector field
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Description
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The VectorField(v, c) command constructs a vector field, which is implemented as a Vector with the vectorfield attribute and a coordinate system attribute.
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The vector field is one of the principal data structures of the Vector Calculus package.
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Note that some VectorCalculus procedures require their input to be vector fields, but will accept Vector-valued operators as well; in this case, any input operator will be interpreted as a vector field, and the output will generally also be an operator.
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The other principal data structures of the Vector Calculus package (free Vectors, position Vectors, and rooted Vectors) are not interpreted as constant vector fields.
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If the second parameter, c, is not specified, the default coordinate system is used. In this case, the default coordinate system must be indexed by coordinate names; otherwise, an error is raised.
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If Vectors are displayed in BasisFormat, the basis vectors for a vector field object are displayed using overbars to visually distinguish a vector field from a free Vector.
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The routine evalVF can be used to evaluate a vector field at a point.
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Examples
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Note the overbars on the basis Vectors
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Note that the Divergence procedure accepts a Vector-valued operator in place of a vector field.
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| (9) |
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