SetScale image from a poly

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I have an image that is from a crystal spectrometer.

One axis is energy (set by calibrating several points).

I would like to display that on the graph. When using setscale I do not see how to get beyond a line for teh axis. When I display waves I plot one wave versus its calibration data, but on on image I am lost.
if the scaling of the image isn't linear, use a separate wave to provide x and or y coordinates.

The trick is that the coordinates define the edges of the image pixels, so a 100 row image would need an X wave defining 101 x values.
Same for y.

AppendImage matrix  vs {xWaveName, yWaveName }

DisplayHelpTopic "Image X and Y Coordinates"


--Jim Prouty
Software Engineer, WaveMetrics, Inc.

May 6, 2016 at 02:34 pm - Permalink

Thanks...

So one is displaying the data with a different "dimension and unit" but the data are still indexed according to teh old convention...

I ahve found that I now have a wave:
x d
-30 1
-20 2
-10 3
0 4
10 5
20 6
30 7

the point values are 0-6 the x values are -30 to 30 the data are 1-7

I want to then make a new x scaling:

where i take x values = const+1.5*x+3*x^2+...

How do I operate on the x values?

This crops up as I have teh image. I did a calibration and then the line profiles have the positional calibration related to them. This comes about as I first must do a spatial calibration then space to energy transformation.

I seem to be lost

Thanks

May 6, 2016 at 03:17 pm - Permalink

this is teh data set in particular...if I cant have teh scale in teh image be in distances then take a lineout which has x values in distance and then convert that into energy based on a calibration I would be golden. But I am not sure how to operate on teh index wave solely
energy calibration.pdf (23.41 KB) image.pdf (2.47 MB) lineout_distance.pdf (23.72 KB)

May 6, 2016 at 03:29 pm - Permalink

I suggest that you have two options.

* Use the Transform Axis package. This will put a second axis on your line graph, likely at the top of the graph. The second axis will show energy as transformed from the x-value of the data set. The advantages are, this does not change your raw data and it shows the two scales simultaneously. The disadvantage is, when you want to display or do analysis based entirely on energy rather than position, the use of an additional axis could be confusing. See the Transform Axis package for further details.

* Create a separate x-wave of energy and replot the line profile versus it. The advantage is, you will see the line profile only versus energy and not with the additional "position" scale. The disadvantage is, any further operations always have to remember to use both y and x data waves (i.e. peak fitting operations). To do this requires something as easy as ...

duplicate/O line energy
energy = k0 + k1*x + k2*x^2 + ...
display line vs energy as "Profile Energy Plot"



--
J. J. Weimer
Chemistry / Chemical & Materials Engineering, UAH

May 7, 2016 at 08:34 am - Permalink