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To optimize the fitting goal (74),
module `unwrap()` uses the conjugate-direction method
like the modules `cgmeth()` and
`invstack()` .
unwrapInverse 2-D gradient
An open question is whether the required number of iterations is reasonable
or whether we would need to uncover a preconditioner
or more rapid solution method.
I adjusted the frame size
(by the amount of smoothing in Figure )
so that I would get the solution in about ten seconds with 400 iterations.
Results are shown in
Figure .
**veshigh90
**

Figure 5
Estimated altitude.

To summarize, the input is the phase map
Figure
and the output is the altitude map in
Figure .
Oddly, the input looks maybe nicer than the output
because it already looks something like a contour plot.
So if we have a beauty contest, then the input beats
the output, but if you need to have
the (normalized) altitude *h*(*x*,*y*),
not the phase of *e*^{ih(x,y)},
then you need to solve the least squares problem.

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Stanford Exploration Project

4/27/2004