Accuracy assessment report — xDEM

xDEM version: 0.1.dev729

Date: 13/01/2026 15:02:39

Computing time: 23.89 seconds

Elevation datasets

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Information about inputs

InformationValue
reference_elev{'path_to_elev': '../../../xdem/example_data/Longyearbyen/data/DEM_2009_ref.tif', 'from_vcrs': 'None', 'to_vcrs': 'None', 'downsample': '1'}
to_be_aligned_elev{'path_to_elev': '../../../xdem/example_data/Longyearbyen/data/DEM_1990.tif', 'path_to_mask': '../../../xdem/example_data/Longyearbyen/data/glacier_mask/CryoClim_GAO_SJ_1990.shp', 'from_vcrs': 'None', 'to_vcrs': 'None', 'downsample': '1'}
sampling_gridreference_elev

Coregistration user configuration

InformationValue
step_one{'method': 'LZD', 'extra_information': "{'subsample': 10000}"}
processTrue

LZD inputs

InformationValue
random{'subsample': '10000', 'random_state': '42'}
fitorbin{'fit_minimizer': 'least_squares', 'fit_loss_func': 'linear'}
iterative{'max_iterations': '200', 'tolerance': '0.01'}
specific{}
affine{'only_translation': 'False'}

LZD outputs

InformationValue
affine{'centroid': '(515650.83, 8663888.17, 353.11)', 'matrix': '[[ 9.99999985e-01 1.17578419e-04 -1.30099078e-04 1.02548967e+01]\n [-1.17594385e-04 9.99999986e-01 -1.22719549e-04 1.90590312e+00]\n [ 1.30084647e-04 1.22734846e-04 9.99999984e-01 -1.93544013e+00]\n [ 0.00000000e+00 0.00000000e+00 0.00000000e+00 1.00000000e+00]]', 'shift_x': '10.25', 'shift_y': '1.91', 'shift_z': '-1.94'}
random{'subsample_final': '10000'}

Statistics

Data Median NMAD Valid count
Aligned elevation 363.338928 291.801208 1309704
Difference before coreg 2.766407 3.805830 1312020
Difference after coreg 0.254444 2.403943 1309704

Elevation differences

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Differences histogram

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