why does this call to ListPlot3D crash the kernel?

[Michael Stern]

I have a matrix of 48 three-number lists that is for some reason killing
the kernel when I try to graph it.

flatvaluematrix={{3525206400, -0.001, 33.0746}, {3525206400, 0.005,
12786.3}, {3525206400, 0.011, 38541.}, {3525206400, 0.017,
65163.}, {3527798400, -0.001, 23.5575}, {3527798400, 0.005,
12559.3}, {3527798400, 0.011, 38463.9}, {3527798400, 0.017,
65143.1}, {3530476800, -0.001, 15.0909}, {3530476800, 0.005,
12299.7}, {3530476800, 0.011, 38387.1}, {3530476800, 0.017,
65126.1}, {3533068800, -0.001, 8.58963}, {3533068800, 0.005,
12022.3}, {3533068800, 0.011, 38318.7}, {3533068800, 0.017,
65113.8}, {3535747200, -0.001, 4.53454}, {3535747200, 0.005,
11762.1}, {3535747200, 0.011, 38267.4}, {3535747200, 0.017,
65106.6}, {3538425600, -0.001, 1.87709}, {3538425600, 0.005,
11474.7}, {3538425600, 0.011, 38224.9}, {3538425600, 0.017,
65102.2}, {3540931200, -0.001, 0.562167}, {3540931200, 0.005,
11178.4}, {3540931200, 0.011, 38195.7}, {3540931200, 0.017,
65100.3}, {3543609600, -0.001, 0.110118}, {3543609600, 0.005,
10895.5}, {3543609600, 0.011, 38179.8}, {3543609600, 0.017,
65099.8}, {3546201600, -0.001, 0.00755001}, {3546201600, 0.005,
10603.2}, {3546201600, 0.011, 38172.9}, {3546201600, 0.017,
65099.6}, {3548880000, -0.001, 0.0000273622}, {3548880000, 0.005,
10312.}, {3548880000, 0.011, 38171.4}, {3548880000, 0.017,
65099.6}, {3551472000, -0.001, 1.06357*10^-11}, {3551472000, 0.005,
10119.2}, {3551472000, 0.011, 38171.3}, {3551472000, 0.017,
65099.6}, {3554150400, -0.001, 0.}, {3554150400, 0.005,
0.}, {3554150400, 0.011, 0.}, {3554150400, 0.017, 0.}};

ListPlot3D[flatvaluematrix]

Kaboom!

This fails under both Windows Mathematica 8.01 and Windows Mathematica 7.

Can anybody help?

Thank you.

MS

(For those who are curious, the first number in the list is a date, the
second is an interest rate spread, and the third is the value of a
financial instrument on the specified date and the given spread).

[Heike Gramberg]

In my version of Mathematica, the kernel doesn't crash, but I do get the
following warning:

ListPlot3D::ntri: The data generates an inconsistent triangulation. You
can perturb the data to make it valid. >>

and Mathematica returns the unevaluated input. I suspect that the
problem is the discrepancy between the
range of y-values and the range of x-values which differ by a order 9.
One way to get the plot to word is to
do something like this

maxmin = {Min[#], Max[#]} & /@ Transpose[flatvaluematrix][[{1, 2}]];

rescaled =
Transpose[{Rescale[flatvaluematrix[[All, 1]]],
Rescale[flatvaluematrix[[All, 2]]],
flatvaluematrix[[All, 3]]}];

gr = ListPlot3D[
rescaled, PlotRange -> All];

gr /. GraphicsComplex[a__] :>
GeometricTransformation[GraphicsComplex[a],
RescalingTransform[{{0, 1}, {0, 1}, {0, 1}},
Append[maxmin, {0, 1}]]]

This basically rescales the x,y-values of the data points so that they
lie in the range {0,1}, plots the rescaled
points, and then stretches the graph in the x and y-direction back to
the original values of x and y.

Heike

[McHale, Paul]

The range of the biggest to smallest number could be too great.

flatvaluematrixnew=Map[#*{0.000001,1,1}&,flatvaluematrix]
ListPlot3D[flatvaluematrixnew]

Works just fine. Can you scale this way and still get useful information?
ListPlot[] has no problem which is odd.

p1=Map[ListPlot[#,Joined->True]&,flatvaluematrix];
Show[p1]

Maybe it is a limitation in the surfacing algorithms. Not sure...

Paul McHale | Electrical Engineer, Energetics Systems | Excelitas Technologies Corp.

Phone: +1 937.865.3004 | Fax: +1 937.865.5170 | Mobile: +1 937.371.2828
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Thank you

[Joseph Gwinn]

In article <j2iel0$bis$1...@smc.vnet.net>,
Michael Stern <nycs...@gmail.com> wrote:

Mathematica 8.0.1.0 on MacOS 10.6.8 does not crash, but it yields an odd error
message:

"ListPlot3D::ntri: The data generates an inconsistent triangulation. You
can perturb the data to make it valid."

The complaint basically means that the dataset cannot be interpreted as
the description of a surface. Plot3D does not do point clouds.

Do you mean to plot points? If so, you need an added step, using Map[]
to make these into points, and Graphics to show them. For instance:

pointlist=Map[Point[#]&,flatvaluematrix];
Graphics3D[pointlist]

Joe Gwinn

[Oleksandr Rasputinov]

On Thu, 18 Aug 2011 08:23:12 +0100, Michael Stern <nycs...@gmail.com>
wrote:

I can reproduce your observation in 7.0.1, but in 8.0.1 there is no crash
and the input returns unevaluated with the message:

ListPlot3D::ntri: The data generates an inconsistent triangulation. You
can perturb the data to make it valid.

But I am not quite sure what one is expected to do about this in practice.
However, plotting an interpolation of the data does work (though the
output seems rather uninteresting):

int = Interpolation[flatvaluematrix];
Plot3D[
int[x, y],
{x, Sequence @@ int[[1, 1]]} // Evaluate,
{y, Sequence @@ int[[1, 2]]} // Evaluate
]

(Mathematica 5.2 produces a plot in response to your input, although it
seems to be incorrect.)