Pith Number

pith:4NS7DAI3

pith:2022:4NS7DAI345OKVGVT4PCRHX7XJR

not attested not anchored not stored refs pending

Impact of correlated observation errors on the convergence of the conjugate gradient algorithm in variational data assimilation

Anthony T. Weaver, Oliver Guillet (CNRM), Olivier Goux (ISAE-SUPAERO), Selime G\"urol, Youssef Diouane (EPM)

arxiv:2212.02305 v1 · 2022-12-05 · math.NA · cs.NA

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{4NS7DAI345OKVGVT4PCRHX7XJR}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-07-05T05:22:22.914361Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e365f1811be75caa9ab3e3c513dff74c6d66f51a1f92aadde139a91f37fdbb14

Aliases

arxiv: 2212.02305 · arxiv_version: 2212.02305v1 · doi: 10.48550/arxiv.2212.02305 · pith_short_12: 4NS7DAI345OK · pith_short_16: 4NS7DAI345OKVGVT · pith_short_8: 4NS7DAI3

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/4NS7DAI345OKVGVT4PCRHX7XJR \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: e365f1811be75caa9ab3e3c513dff74c6d66f51a1f92aadde139a91f37fdbb14

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "5036cd49fc67f62cfa10574c87a45e19970d86c845b1f51b14d67566f4096dd0",
    "cross_cats_sorted": [
      "cs.NA"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.NA",
    "submitted_at": "2022-12-05T14:32:32Z",
    "title_canon_sha256": "9852e1cc0d63c606dae590a70d9bc760b21a79b859e0901dcf8ce822462c0fc3"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2212.02305",
    "kind": "arxiv",
    "version": 1
  }
}