Questions tagged [minimum-weight-perfect-matching]

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Can you give an intuitive idea behind how the Minimum Weight Perfect Matching (MWPM) decoder work?

The Minimum Weight Perfect Matching (MWPM) decoder seems to be the most popular choice for decoding error syndromes in Surface Code quantum error correction. Can anyone give an intuitive idea of how it works, with an example?
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Simple example for the sub-optimality of MWPM vs Maximum likelihood decoder

I understand that the Minimum Weight Perfect Matching (MWPM) decoder tries to identify the single most probable error configuration, while a maximum likelihood decoder aims to find the most probable coset of errors (those equivalent up to a…
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Why logical error rates from BP-OSD and MWPM are so different?

I'm plotting logical error rates for different codes and comparing two decoders (BP-OSD and MWPM) For each code I calculate logical error rates by preparing the code in $|0\rangle_L$ state with encoding circuit ($p_{L_0}$), measuring stabilizers…
tomek
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is there a pure c/c++ MWPM decoder

I understand that PyMatching has a main c++ core with all sorts of python wrappers. Is there an example that shows how to use it in a pure c++ environment. I think the python part integrates an interface to STIM (which also has a c/c++ version).…
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PyMatching in presence of qubit error for the repetition code

I'm considering the repetition code in presence of measurement and qubit error as discussed in SEC IV B of this paper. I am trying to use pymatching for the syndrome decoding using mwvp in presence of qubit error, so it should work but it doesn't.…
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How can we decode non CSS codes like XZZX code with Pymatching?

I am trying to use Pymatching to decode some non CSS codes like the XZZX code. Pymatching is a perfect decoder for CSS codes, which can work effectively even of a large code distance. I have tried to decode XZZX code with Pymatching (circuits…
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Some problems when trying to reproduce the threshold result of simulation of surface code

Recently I am trying to do some simulations on the surface code to get the empirical curve of logical error(P_L) corresponding with physical error rate(p) and code distance(d) as Towards practical classical processing for the surface code do.…
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Pymatching Toric Code vs Surface Code

I am looking the example of toric code in Pymatching. Here is the code: import numpy as np import matplotlib.pyplot as plt from scipy.sparse import hstack, kron, eye, csr_matrix, block_diag def repetition_code(n): row_ind, col_ind =…
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Why minimum weight in the minimum weight perfect matching?

I am studying quantum decoding, especially for minimum weight perfect matching. I wonder after finding perfect matching (syndrome graph referred by sparse Blossom), why do we need to select minimum weight? Is there any specific reason for selecting…
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Do detection events mean temporal and spatial coordinates?

In pymatching, the check_matrix structure is for stabilizers rather than measurement outcome of stabilizers. I want to plot "matching" for my measurement outcomes.To do that, I need to convert the measurement results into detection events. Here I…