{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:MVGVRR4JOKJJ53KEJFK5RBF23R","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"86451863e431c78965a24e30e9481e81b1a61ba6def47eb5b9bf747f0ef835ca","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2017-12-15T10:21:16Z","title_canon_sha256":"092d541f211e010e917a87ce6590844358dfd4c6a23566caff5450575e531afb"},"schema_version":"1.0","source":{"id":"1712.05602","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1712.05602","created_at":"2026-05-18T00:11:57Z"},{"alias_kind":"arxiv_version","alias_value":"1712.05602v2","created_at":"2026-05-18T00:11:57Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1712.05602","created_at":"2026-05-18T00:11:57Z"},{"alias_kind":"pith_short_12","alias_value":"MVGVRR4JOKJJ","created_at":"2026-05-18T12:31:31Z"},{"alias_kind":"pith_short_16","alias_value":"MVGVRR4JOKJJ53KE","created_at":"2026-05-18T12:31:31Z"},{"alias_kind":"pith_short_8","alias_value":"MVGVRR4J","created_at":"2026-05-18T12:31:31Z"}],"graph_snapshots":[{"event_id":"sha256:8b009f8ac15a6c8ad7c3ec8f67ef37b417884b9c47f1229f3a631de60f32626f","target":"graph","created_at":"2026-05-18T00:11:57Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"This paper describes a new MATLAB software package of iterative regularization methods and test problems for large-scale linear inverse problems. The software package, called IR Tools, serves two related purposes: we provide implementations of a range of iterative solvers, including several recently proposed methods that are not available elsewhere, and we provide a set of large-scale test problems in the form of discretizations of 2D linear inverse problems. The solvers include iterative regularization methods where the regularization is due to the semi-convergence of the iterations, Tikhonov","authors_text":"James G. Nagy, Per Christian Hansen, Silvia Gazzola","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2017-12-15T10:21:16Z","title":"IR Tools: A MATLAB Package of Iterative Regularization Methods and Large-Scale Test Problems"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1712.05602","kind":"arxiv","version":2},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:691a63b39403255b0e1d627f39fce642b1b9fd8c07e412dd6cba3da45677ccdf","target":"record","created_at":"2026-05-18T00:11:57Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"86451863e431c78965a24e30e9481e81b1a61ba6def47eb5b9bf747f0ef835ca","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2017-12-15T10:21:16Z","title_canon_sha256":"092d541f211e010e917a87ce6590844358dfd4c6a23566caff5450575e531afb"},"schema_version":"1.0","source":{"id":"1712.05602","kind":"arxiv","version":2}},"canonical_sha256":"654d58c78972929eed444955d884badc6ef6c37e749cc6b07d47390dadd5ed3e","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"654d58c78972929eed444955d884badc6ef6c37e749cc6b07d47390dadd5ed3e","first_computed_at":"2026-05-18T00:11:57.650292Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:11:57.650292Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"pBucUS27bOGp6AdizakINO8H2+u0I34SPfH88gqx7ChWaKIgRdtlSI3JcxmLkbK5P6Q9CIT0yQvuxiFoszd1BQ==","signature_status":"signed_v1","signed_at":"2026-05-18T00:11:57.651021Z","signed_message":"canonical_sha256_bytes"},"source_id":"1712.05602","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:691a63b39403255b0e1d627f39fce642b1b9fd8c07e412dd6cba3da45677ccdf","sha256:8b009f8ac15a6c8ad7c3ec8f67ef37b417884b9c47f1229f3a631de60f32626f"],"state_sha256":"813fe562dad1b0fde2d8b7c0883c333cddf560f98673d1f8d6a37adc9cb650d1"}