non-linear Scaling of 2D wave
fasix
Wed, 09/19/2012 - 11:14 am
I have one "waveX" wave and many spectra "waveY_angle" for different angles.
I have create a matrix (2D wave) with columns equals to the number of elements in "waveX", and rows equals to the numbers of angles.
The angles is equally spaced (1 degree), but the "waveX" in not equally spaced.
I have change the scaling of the 2D wave (matrix) for the Y axis with "start and end" option, and it is work; but for the X axis the "start and end" scaling does not work properly because the "waveX" is not equally spaced.
Now, I would know if there is some solution to my problem.
If I understand correctly, then you have this ...
[angle] 0 1 1.2 2.5 6.7
0
1 [ data matrix ]
2
3
... where [angle] can be set implicitly by wave scaling but (energy) cannot be.
You might then also want to attach a row to the top or bottom of your matrix that explicitly defines (energy) values, something like this ...
NaN 0 1 1.2 2.5 6.7 <-- explicitly defined in first "row"
0
1 [ data matrix ]
2
3
--
J. J. Weimer
Chemistry / Chemical & Materials Engineering, UAHuntsville
September 19, 2012 at 05:55 pm - Permalink
I have attached a igor file with the next wave:
1) "prova": 2D wave (just calibrate in X axis, but not in Y axis)
2) "waveX": the not equally spaced wave corrisponding with the wavelength of the rows (spectra) of the matrix "prova"
3) "waveX_mod" the equally spaced wave with the same extremes of the "waveX" and the same numbers of elements of "waveX" and the columns of "prova"
Help me, please
September 20, 2012 at 01:50 am - Permalink
In Igor, you can use that wave directly to establish the X values for a contour plot or for a waterfall plot. You can also use it for the X values if you do a curve fit to the matrix.
If you want to make an image plot, if you supply an X wave with unequally spaced values, Igor interprets the values as specifying the edges of the image cells. Consequently you must provide N+1 values in the X wave used with an image plot.
I just looked at your experiment file (which I should have done first) and I see that you have made an image plot, so you need one more point in your X wave. If you have the beta of our latest version of Igor (6.30b01) you can read a nice description of this by executing this command on Igor's command line:
DisplayHelpTopic "Image X and Y Coordinates - Unevenly Spaced"
John Weeks
WaveMetrics, Inc.
support@wavemetrics.com
September 20, 2012 at 04:38 pm - Permalink
it works
PS: I would like to know if this feature has been added in beta or is there even in the stable version.
hello and thank you
September 21, 2012 at 01:44 am - Permalink
John Weeks
WaveMetrics, Inc.
support@wavemetrics.com
September 21, 2012 at 09:56 am - Permalink