On Mar 21, 2013, at 4:40 PM, Waichler, Scott R wrote:
I have a 3D field of a scalar variable (x, y, z, value). Is there a way to
generate a vector field from this data--gradient at defined points? I found
the rasterVis package for 2D data, but as yet nothing for 3D data.
Can't you just think of 'value' as a potential and then differentiate (using
sweep?) along the three principal axes to construct the partial derivatives
(eg. diff(value)/diff(x) at constant y and z) which would then form the
components of the vector field? That's how one goes from gravitational or
electrical potential to the corresponding vector fields. E - grad(V),
As always: Data would help clarify.
--
David Winsemius
Alameda, CA, USA
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