> Full Name: Dave Dempsey > Email Address: address@hidden > Organization: San Francisco State University > Package Version: 4.1 build date:2013-08-02 18:38 UTC > Operating System: Mac OS X > Hardware: Java: home: > /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home version: > 1.6.0_51 j3d:1.5.2 fcs (build4) > Description of problem: Creating display: Contour Plan View > TypeError: div() takes exactly 1 argument (2 given) > org.python.core.PyException > > I'm calculating the Laplacian of 500 mb heights from the NAM model (just to > see if I can do it). To do this, I created a new formula, called "Laplacian > operator", and put it in the Grids group. It is defined simply as "lap(S)". > The formula "lap(S)" is defined in the Java formula library. > > Applying the new formula to a NAM 500 mb height field and trying to plot > contours of it produced the error message above. > > For reference: lap(S) is defined in the Jython library as > div(ur(grads),vr(grads)), where grads = grad(S) and S is a scalar field. > > In turn, div is defined as add(ddx(ur(V), ddy(vr(V)), where V is a vector > field. > > Then, I tried creating my own Laplacian operator formula. It bypasses the > "div" formula and calculates the Laplacian from > a scalar field directly, although it appears to use the same formula as > lap(S) and > > add(ddx(ur(grad(S))),ddy(vr(grad(S)))) > > Unlike lap(S), this works. > > So, why would lap(S) fail where my algorithmically equivalent version > succeeds? Dave, I think your equivalent version is corrected. The problem with the original lap(S) is that it should call div(grads) or add(.....). I will fix it now. Yuan > > I've attached a bundle that creates a plot using the successful version of > the Laplacian operator (called "Laplacian operator" in the Grids group of > forumulas). > > -- Dave > > > > > > ****************** > Stack trace: > Traceback (most recent call last): > File "<string>", line 1, in <module> > File "<string>", line 208, in lap > TypeError: div() takes exactly 1 argument (2 given) > > > Ticket Details =================== Ticket ID: PKQ-297414 Department: Support IDV Priority: Normal Status: Open
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