| 11 Jan 2014 12:08 PM |
|
|
Hello,
I am having trouble creating a 2-D scatterplot of 2 bands of vegetation fractions (the result of linear spectral unmixing). I keep getting an error that says, "Cannot create scatter plot without valid pixels in the display". The only thing I can think of is that the data are in floating point format. Does this affect ENVI's ability to create a scatter plot? If so, how do I convert floating point data to integers without losing information?
Thanks
|
|
|
|
Deleted User
Basic Member
Posts:228  
| 14 Jan 2014 09:34 AM |
|
|
Floating point values are fine in a scatter plot. I just did a quick unmixing and tried making a scatter plot from the resulting abundance images, which are also floating point, and it worked just fine. You may want to contact Exelis VIS Tech Support or your local distributor directly to track down what is going wrong in your case. It sounds like it may have something to do with your specific image file.
Peg
Exelis VIS
|
|
|
|
Deleted User
Basic Member
Posts:228
| 14 Jan 2014 09:38 AM |
|
|
I just noticed that there is a known problem in the current version of ENVI that results in this error when you place a subset of an image in a view that contains also the original image. If you then try to make a 2D scatter plot, you get the message you reported. The way to work around this, until the problem is resolved, is to remove both images from the view, then display just the subset. At that point, you should be able to make a 2D scatter plot without running into errors.
Peg
Exelis VIS
|
|
|
|
Deleted User
New Member
Posts: 
| 14 Jan 2014 03:21 PM |
|
|
Peg,
Thanks for your reply. I was able to fix my problem by creating a layer stack and the "exclusive" radio button so that the layers were exactly the same extent.
I do have another question: is there a way to insert a 1:1 line in a 2-D scatterplot in either ENVI classic or ENVI 5? I do not know how to program in IDL and was hoping that I could do this using the GUI.
|
|
|
|