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Julian
Posts:
3
Registered:
3/20/14


Re: Colormapping Matrix with 9990% zeros and several peaks
Posted:
Mar 20, 2014 4:43 PM


"Kelly Kearney" wrote in message <lgfetg$s9h$1@newscl01ah.mathworks.com>... > "Julian" wrote in message <lgfdru$p68$1@newscl01ah.mathworks.com>... > > I have a Matrix with values ranging from 0 to 2*pi, size of this matrix is 2000² (just as a reference) and there are very few values in there (a maximum of 2*32²). > > > > Now i need a method or an idea to visualize this. What I have so far: > > > > figure; > > image(Z1) %Z1=matrix<=size=2000*2000 > > colormap(jet) > > > > Of course Finding those pixels is hard and they aren't a very good representation. > > > > So my thougth was to make a convolution of the matrix with a 2Dgaussian curve (curve beeing normed at maximum to 1). > > But that seems a very crude methode and I have to use this a lot. > > > > Furthermore I'd like it to exclude all zeros ( colormap from white (0) to blue(lowest) to red (highest)). > > > > I really hope for some ideas or usefull matlab methods. > > > > Thanks in advance > > I think a scatter plot would be your best bet. This function > > http://kellyakearney.net/matlabdoc/GeneralUtilities/spycolor.html > > is a little wrapper I wrote that creates a scatter plot for just this type of sparse data (and it will exclude 0s by default).
Thank you that's perfect actually much is better than what I had in mind.



