cwcustom colormap style on small range when overall range is large

[TheBillyBobJr]

Hi, I am attaching the colormap example that David Mc., and NI Applications Engineer sent me a while back explaining using colorlookup tables. I modified this project to have a data range of 0 to 10001. There is a sin wave located in the range 9999 to 10001 and a single like of 0's to make the range huge of the overall scale. The problem I have is, I set my values of my custom colormap to being 9999, 10000, and 10001 respectively and they don't display in their ranges. If the 0's of the overall range are taken out so that the range only encompasses -1 to 1, this method works fine.

Am I doing something wrong? When a values is assigned to the colorlookup table, the respective value of the data shou
ld be that color correct? Why does this not work on a small range if the overall range is larger. It seems to me that it should.

Thanks,
Kevin

[David Mc]

Hi Kevin,

When using a custom color map, the 3D Graph decimates the data to display as much of the data range it can. It doesn't take the axes ranges into account, it just tries to plot the surface over the entire range.

The large range you are using (0 to 10001 = 10001 point range) pretty much ends up looking like one point at the end of the spectrum. If you switch to a smaller range like 0 to 101 (= 101 point range), you can see how the smaller range can be better displayed by the 3D Graph.

I would suggestion you filter your data, and only plot the points that matter to you (i.e. the ones that fit inside your 3D axis range).

However, the situation you've run into might be a good use case for an enhancement to the 3D Graph: allow you to programmatic
ally control the decimation by setting a "window size". You can visit http://ni.com/contact and click "Product Feedback" to submit a product suggestion for this and any other features you'd like to see.

David Mc.
NI Applications Engineer