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I'm trying to use the QGIS plugin vector affine transformation to translate a shapefile with wrong coordinates using the right coordinates of another shapefile. It looks like thisenter image description here

I read other answers to this problem but still my transformation does not work. I take the coordinates of 3 points of the original shapefile:

396379.157,4992456.237
396434.636,4992428.498
396494.740,4992398.908

I take the coordinates of the same 3 points of the target shapefile:

396373.609,4992445.141
396431.169,4992416.939
396492.312,4992386.888

Then from online solver I get parameters to include into the transformation matrix:

U = -0.276
V = -2.628
W = 13625340.309
X = 19.103
Y = -197.695
Z = 380203686.883

or using another solver:

q = -0.279
r = -2.634
s = 13657434.35
t = 48.227
u = 158.434
v = 177246147.891

then I complete the QGIS transformation matrix 

 -0.279 -2.634 13657434.35
48.227 158.434 177246147.891

But what happens is not a translation and it looks like this enter image description here

What am I doing wrong?

Is it because my transformation does not include rotation?

Ideas about how can I solve this problem?

ggg
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1 Answers1

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I found a solution. I understood that what I need is just a translation, I don't need to rescale or rotate the shapefile. Therefore, instead of using the whole matrix of the affine transformation plugin (which continues to give incorrect results) I just took the coordinates of one point in the original (wrong) shapefile, (396460.52513,4992655.01317) then I took the coordinates for the same point in the target shapefile (396374.45124,4992446.61507) and i calculated the difference (x:-86,07389 y: -208,3981). I then used the transformation matrix of Affine Transformation filling 1 0 and the last column with my "difference of coordinates": 1 0 -86,07389 0 1 -208,3981 And it works!

ggg
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