# libdlr: Efficient imaginary time calculations using the discrete Lehmann representation

@article{Kaye2021libdlrEI, title={libdlr: Efficient imaginary time calculations using the discrete Lehmann representation}, author={Jason Kaye and Hugo U. R. Strand}, journal={ArXiv}, year={2021}, volume={abs/2110.06765} }

We introduce libdlr, a library implementing the recently introduced discrete Lehmann representation (DLR) of imaginary time Green’s functions. The DLR basis consists of a collection of exponentials chosen by the interpolative decomposition to ensure stable and efficient recovery of Green’s functions from imaginary time or Matsbuara frequency samples. The library provides subroutines to build the DLR basis and grids, and to carry out various standard operations. The simplicity of the DLR makes…

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