A routine for transorming between X,Y coordinates measured on the ACAM and the LRS2 images from lmap. You can go from ACAM to LRS2 or LRs2 to ACAM. Both the LRS2 channels, B and R, are supported. As of Aug8,2016, this routine supports two methods of coordinate transformations (coefs = uses two independent linear equations, trs = translation, rotation, and scaling).
% % lrs2_acam_xy Usage: lrs2_acam_xy file.xy trs LRS2 ACAM B arg1 = file with simple X,Y values arg2 = transformation file type (coefs,trs) arg3 = name of system transforming from (LRS2,ACAM) arg4 = name of system transforming to (LRS2,ACAM) arg5 = name of LRS2 channel being used (R,B) A typical XY file might look like: % cat xy.lrs2 # XY LRS2-R # data -2.001133 -3.227448 -0.237180 -1.144305 2.920943 -1.446680 0.098678 0.485128 0.619500 1.627367 0.283495 -2.437880 -3.328190 1.997003 The output (to standard out) might look like: % lrs2_acam_xy xy.lrs2 trs LRS2 ACAM R 719.088 545.778 727.338 551.607 727.239 563.343 733.450 552.320 737.827 553.871 722.737 553.944 737.918 539.202Note that at this time, the input XY files have different formats for the "coefs" and the "trs" methods. A trs approach will require the XY file to have a header delimited by a "# data" line. The coefs approch simply takes two raw columns of numbers. I have considered adding headers to the coefs-related methods, but these routines are buried ina lot of different scripts that are actively being used in HET obaserving. I have elected to leave this source code alone for now.
As an aside, but relevant here, we might want to compare these coordinates with another file of LRS2 positions (XY.lrs2_B). Here is a quick way to do it:
NOTE: We must have two XY files with NO HEADERS.
% cat xy.1
719.088 545.778
727.338 551.607
727.239 563.343
733.450 552.320
737.827 553.871
722.737 553.944
737.918 539.202
% cat xy.2
720.57 545.90
727.34 552.20
727.68 563.33
733.45 552.32
738.76 554.00
721.35 555.98
736.41 539.27
% xy_tranrot_res.sh xy.1 xy.2
1.115 0.742 7
These quantities are the standard deviations in X, and Y, and the number of points compared.
A very useful file from this last run is:
% cat xy_tranrot_res.resids_list
# List of XY residuals from xy_tranrot_res.sh
line X1 Y1 X2 Y2 dX dY Res Res_norm
1 719.088 545.778 720.570 545.900 -1.482 -0.122 1.487 1.1103
2 727.338 551.607 727.340 552.200 -0.002 -0.593 0.593 0.4428
3 727.239 563.343 727.680 563.330 -0.441 0.013 0.441 0.3294
4 733.450 552.320 733.450 552.320 0.000 0.000 0.000 0.0000
5 737.827 553.871 738.760 554.000 -0.933 -0.129 0.942 0.7033
6 722.737 553.944 721.350 555.980 1.387 -2.036 2.464 1.8395
7 737.918 539.202 736.410 539.270 1.508 -0.068 1.510 1.1272
We can use the last file above to identify problematic points.