Reducing acquisition time and radiation damage: data-driven subsampling for spectro-microscopy

Meier, M.; Lazzarino, L.; Shustin, B.; Al Daas, H.; Quinn, P.

doi:10.1107/S1600577526006491

Figure 2
A matrix of exact rank S (in this case S = 2) can be represented using just S of its columns and S of its rows using the CUR decomposition. The only requirement is that the rows and columns are linearly independent. Here, the construction of $[{\bf{C}}]$ , $[{\bf{U}}]$ and $[{\bf{R}}]$ from $[{\bf{D}}_{\rm{exact}}]$ is shown with color: $[{\bf{C}}]$ consists of the burgundy columns of $[{\bf{D}}_{\rm{exact}}]$ , $[{\bf{R}}]$ of the two purple row, and $[{\bf{U}}]$ of the two-by-two matrix where the rows and columns overlap. Experimentally, $[{\bf{C}}]$ represents two pixels measured for all energies and $[{\bf{R}}]$ represents two energies for which all pixels are measured.

JOURNAL OF
SYNCHROTRON
RADIATION

ISSN: 1600-5775

Volume 33| Part 5| September 2026| Pages 1440-1454

https://doi.org/10.1107/S1600577526006491

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