"boxcar function" meaning in English

{
  "etymology_text": "The graph resembles a rectangular boxcar on a railway line.",
  "forms": [
    {
      "form": "boxcar functions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "boxcar function (plural boxcar functions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Functions",
          "orig": "en:Functions",
          "parents": [
            "Algebra",
            "Calculus",
            "Geometry",
            "Mathematical analysis",
            "Mathematics",
            "Formal sciences",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Mathematics",
          "orig": "en:Mathematics",
          "parents": [
            "Formal sciences",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Any function whose value is zero except for a finite part of its argument for which it has a constant non-zero value"
      ],
      "hypernyms": [
        {
          "word": "window function"
        }
      ],
      "id": "en-boxcar_function-en-noun-WRpsyrO1",
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "value",
          "value"
        ],
        [
          "zero",
          "zero"
        ],
        [
          "finite",
          "finite"
        ],
        [
          "argument",
          "argument"
        ],
        [
          "constant",
          "constant"
        ]
      ],
      "raw_glosses": [
        "(mathematics) Any function whose value is zero except for a finite part of its argument for which it has a constant non-zero value"
      ],
      "related": [
        {
          "word": "square wave"
        }
      ],
      "topics": [
        "mathematics",
        "sciences"
      ],
      "wikipedia": [
        "boxcar function"
      ]
    }
  ],
  "word": "boxcar function"
}

{
  "etymology_text": "The graph resembles a rectangular boxcar on a railway line.",
  "forms": [
    {
      "form": "boxcar functions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "boxcar function (plural boxcar functions)",
      "name": "en-noun"
    }
  ],
  "hypernyms": [
    {
      "word": "window function"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "square wave"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with non-redundant non-automated sortkeys",
        "en:Functions",
        "en:Mathematics"
      ],
      "glosses": [
        "Any function whose value is zero except for a finite part of its argument for which it has a constant non-zero value"
      ],
      "links": [
        [
          "mathematics",
          "mathematics"
        ],
        [
          "value",
          "value"
        ],
        [
          "zero",
          "zero"
        ],
        [
          "finite",
          "finite"
        ],
        [
          "argument",
          "argument"
        ],
        [
          "constant",
          "constant"
        ]
      ],
      "raw_glosses": [
        "(mathematics) Any function whose value is zero except for a finite part of its argument for which it has a constant non-zero value"
      ],
      "topics": [
        "mathematics",
        "sciences"
      ],
      "wikipedia": [
        "boxcar function"
      ]
    }
  ],
  "word": "boxcar function"
}