Curve Matching in Two different Figures

Hi, I have a figure that contains about 10 curves. I have another figure that has only one curve. I want to math one curve figure with one of the curves in the figure that has 10 curves. Both figures have different scale.It is only the curve I want to match. Please how do I do it? Thanks

Regards, Isa

Answer 1

[Jan]

What does "match" exactly mean? Do you want to compare the mean value, the shape, are the curves shifted horizontally or vertically only, do they have the same mean, but different scales, or are the curves equal expect for some noise?

If only the scales (and means) differ, you can "normalize" them by dividing by the maximum absolute value (and subtracting the mean). Then "matching" could mean to find the minimum difference between the single curve and the set of curves. Now "minimum difference" must be defined also: does "distance" mean the sum of the absolute differences of all points, the maximum difference, the mean or minimal difference, the standard deviation of the differences, etc.?

[Isa Isa]

Match in my question means matching the shape of the curve in one curve figure with one of the curves of 10 curves figure by moving the figure with single curve both vertically and horizontally on the 10 curves figure. After the matching I have to read the x and y axes of both figure at certain point on the matched curves.

I hope my explanation is clear. Thanks

Regards Isa

[Jan]

@Isa: At least I still do not understand. Do you want to move the axes by hand until you have the visual impression? What does "reading the x and y axes" exactly mean? Why do you want to move the figure, which is the window, which contains the axes?

[Isa Isa]

Sir, I want to move the whole plot until it matches one of the curves in other figure. I want to juxtapose one figure on another.

Thanks Isa

[Image Analyst]

Do you have the curves as numerical arrays of x and y? Or you have only some kind of figure or bitmap image?

Where did you upload your screenshots to? http://www.mathworks.com/matlabcentral/answers/7924-where-can-i-upload-images-and-files-for-use-on-matlab-answers Also include one that has the desired output. If you can mock something up in Photoshop for us, that would be great.

[Isa Isa]

Thanks. I have standard models put in curves, the curves are in both figure and bitmap image. I have uploaded a typical case please check this link http://imageshack.us/photo/my-images/844/curvematch.jpg/ The curves in blue are the standard curves and the curve in red is the one I have numerical values for its x and y and I want to match it with any of the curves in blue. Thanks Isa

[Jan]

@Isa: Please insert all important information by editing the original question. This is the location, where readers expect them.

You still did not explain what "match" exactly means, but this is the fundamental point of your question. I have the impression, you want to move and resize the axes object with the mouse until you find a visually similar curve. This procedure would be neither reproducible nor exactly enough for a scientific usage. A programmatic comparison and a quantification of the difference is required. But even then there are curves, which have the same distance to two curves of your set. Again I want to stress, that distance between curves have to be defined at first according to your exact needs.

It is much better to keep the complete discussion here in the public forum and not to send further information by email.

[Isa Isa]

Thanks, by match I mean superimposing a plot of the test data on a set of type curves on the same scale and using the characteristic shapes of the type curves to identify an interpretation model for the test data. By this I will be able to select an interpretation model that fits the test data. In the image I sent, there are two dependent variables on both the test data and type curve. curve matching is generally accomplished through automatic fitting of the test data using linear or non-linear regression techniques. Thanks Isa