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Evidence row 120216

Observed , by baseline/1.

Kind
listing
About
source_record x402_bazaar:https://saylorinnovations.com/api/kb/numpy-broadcasting-dtype-overflow-views-nan-pitfalls
Recorded
Previous row
None: the first of its kind about this subject
Body SHA-256
ba723b5b3209874671e20f1840e54f9c67e92333be56cdc9c3b5e1fc124cce36
Leaf
0x0cf168bc924872264f793af070d87c4685f4d644f3251402e0e8e5f22fdc9506

What was observed

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  "owner_address": "0xa2a8df0f7caabea4e120a2568118f141569fc8aa",
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          "name": "USD Coin",
          "note": "Arbitrum settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
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        },
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          "native": true,
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          "quotedLamports": "98648",
          "reference": "7pwArMd5ZzDm1maDqruCvC5TA9weoKGDSEQHrpABtyn6",
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    "description": "NumPy gotchas run live - broadcasting shapes, int8 overflow wraparound, slices as views, NaN poisoning, isclose for floats",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "method": "GET",
            "type": "http"
          },
          "output": {
            "example": {
              "body": "Verified on NumPy 2.2.6: broadcasting a (3,) with a (2,1) array to (2,3), int8 wraparound 100+100 = -56, division by zero giving inf with a warning, slice views, NaN mean versus nanmean, and isclose for floats.",
              "c": "Self-Hosting & Infra",
              "id": "numpy-broadcasting-dtype-overflow-views-nan-pitfalls",
              "t": "NumPy Pitfalls: Broadcasting, Integer Overflow, Views vs Copies and NaN Comparisons"
            },
            "type": "json"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
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                "method"
              ],
              "type": "object"
            },
            "output": {
              "properties": {
                "example": {
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                      "type": "string"
                    },
                    "c": {
                      "description": "Category of the guide",
                      "type": "string"
                    },
                    "id": {
                      "description": "Identifier of the record",
                      "type": "string"
                    },
                    "license": {
                      "description": "License identifier",
                      "type": "string"
                    },
                    "price": {
                      "description": "Price",
                      "type": [
                        "number",
                        "null"
                      ]
                    },
                    "t": {
                      "description": "Title of the guide",
                      "type": "string"
                    }
                  },
                  "required": [
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                    "t",
                    "c",
                    "body"
                  ],
                  "type": "object"
                },
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              "type": "object"
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          "required": [
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    },
    "iconUrl": "https://res.cloudinary.com/bdb-prod/image/upload/c_fill,ar_1:1,w_256,h_256,f_auto,q_auto/v1791811517/bazaar-icons/bc5e2b3d111ebbef.jpg",
    "lastUpdated": "2026-10-24T13:28:10.749Z",
    "quality": {
      "l30DaysTotalCalls": 2,
      "l30DaysUniquePayers": 2,
      "lastCalledAt": "2026-10-24T13:28:10.534Z"
    },
    "resource": "https://saylorinnovations.com/api/kb/numpy-broadcasting-dtype-overflow-views-nan-pitfalls",
    "serviceName": "Saylor Innovations Guide Library",
    "tags": [
      "numpy",
      "python",
      "arrays",
      "dtype",
      "data-science"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "NumPy gotchas run live - broadcasting shapes, int8 overflow wraparound, slices as views, NaN poisoning, isclose for floats"
}

What the leaf hashes

{"body":"ba723b5b3209874671e20f1840e54f9c67e92333be56cdc9c3b5e1fc124cce36","id":120216,"kind":"listing","method":"baseline/1","observed_us":1793025617500928,"prev":null,"subject":"x402_bazaar:https://saylorinnovations.com/api/kb/numpy-broadcasting-dtype-overflow-views-nan-pitfalls","subject_kind":"source_record"}

Proof

Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of (296695 rows).

  1. 0x0cf151acab5ed51dec6d5d1d8f233f90f6b78e90f23b20e3a961ef4b84a56c72
  2. 0x0b846cd860c8d56d38ce62043ca22fd61c375c75b3036771fd246ef07a269688
  3. 0x9e714f54d1de12053faef63348cd6a415cd909c964012f1d35e8123ab1a2d367
  4. 0x3549c5884659743149771d32f1c24c74f454c429a1a187b41698dba243e078e9
  5. 0xa23da4fd039d0f3034a4dbdcc8ebf3c43c56ad86397b8233153e28cae2159aee
  6. 0x5f0d2d449163cc425bc36f47e04ab784bbd8dc4dd0038e90c93f364b91e9275b
  7. 0xd90bd3a7a61fa533b6adf22f04f5d65a60eadd2b54f52afb3d46be5484355467
  8. 0xff763a7641551f6ddb28957b2ee5aae704665f36ab85a1da6db3ac9903f8ab92
  9. 0x5e1a3aef10dac9eae11675ae26e350165e9c6aa5619c1cd34dcab2a806ec5785
  10. 0x7df9268e3c799b09f6f61ac8a493750625b19546a343d4f6c00812722a4e4de6
  11. 0x1dd760089997f06dc5264f791d622a6e7eaf78f6daa715333a752d033cdb2e03
  12. 0x362683225b724b8d2d652a95968c57a6f4199ed4f2ad60900fc3603492f17520
  13. 0x5aefcf9e3d86e125861c0d490079969110eea8fc901ec61531bba10bb58258a1
  14. 0xa96bb9408ce00a0d40ddaba8736257dfce76d5478b131d69db1afdf8a824312b
  15. 0x7ddc2fead128357f881b63e6c7c26d7fbbb84fca6c7c8e0bbfe386de86ca8d39
  16. 0xc6a4d7899a0f442958e26505011190b7cff2483611c1b94eba9043e0ba9ac36e
  17. 0x8c756542e482157df0c36464d75c937b845e4423dbbcfad08f0cf8d5a16b9a13
  18. 0x20704208aa6923d6b2450ef74ede87a6e0265d46447926038fe9506e9e154b2d
  19. 0x9b9ce5b74b9bab5121612ef6b64920a8d453cbf311096a423eef9702747e868a
Day root
0xf43e8dcc3d451a4788b26be904c55e8c4c0fa75c9666796c51db38d37e2c0df8
Chained
0x702d5ac508f08b0d1accf36af25822d8e5660367494edd17a642fb61e158a57a
Published
On Arc Testnet, block 69251483: 0x495162f8936e19f0039918feebe6c307f327cd6bf8c37219620b1970041fa9ae

How to check it · This row as JSON