{
  "__type": "IngestedDoc",
  "__tag": 4010,
  "_content": {
    "Notes": {
      "__type": "Section",
      "__tag": 4015,
      "children": [
        {
          "__type": "Paragraph",
          "__tag": 4045,
          "children": [
            {
              "__type": "Text",
              "__tag": 4046,
              "value": "The probability density function for the Rayleigh distribution is"
            }
          ]
        },
        {
          "__type": "Math",
          "__tag": 4058,
          "value": "P(x;scale) = \\frac{x}{scale^2}e^{\\frac{-x^2}{2 \\cdotp scale^2}}"
        },
        {
          "__type": "Paragraph",
          "__tag": 4045,
          "children": [
            {
              "__type": "Text",
              "__tag": 4046,
              "value": "The Rayleigh distribution would arise, for example, if the East and North components of the wind velocity had identical zero-mean Gaussian distributions.  Then the wind speed would have a Rayleigh distribution."
            }
          ]
        }
      ],
      "title": [],
      "level": 0,
      "target": null
    },
    "Warns": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    },
    "Raises": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    },
    "Yields": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    },
    "Methods": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    },
    "Returns": {
      "__type": "Section",
      "__tag": 4015,
      "children": [
        {
          "__type": "Parameters",
          "__tag": 4026,
          "children": [
            {
              "__type": "DocParam",
              "__tag": 4016,
              "name": "out",
              "annotation": "ndarray or scalar",
              "desc": [
                {
                  "__type": "Paragraph",
                  "__tag": 4045,
                  "children": [
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": "Drawn samples from the parameterized Rayleigh distribution."
                    }
                  ]
                }
              ]
            }
          ]
        }
      ],
      "title": [],
      "level": 0,
      "target": null
    },
    "Summary": {
      "__type": "Section",
      "__tag": 4015,
      "children": [
        {
          "__type": "Paragraph",
          "__tag": 4045,
          "children": [
            {
              "__type": "Text",
              "__tag": 4046,
              "value": "Draw samples from a Rayleigh distribution."
            }
          ]
        }
      ],
      "title": [],
      "level": 0,
      "target": null
    },
    "Receives": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    },
    "Warnings": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    },
    "Attributes": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    },
    "Parameters": {
      "__type": "Section",
      "__tag": 4015,
      "children": [
        {
          "__type": "Parameters",
          "__tag": 4026,
          "children": [
            {
              "__type": "DocParam",
              "__tag": 4016,
              "name": "scale",
              "annotation": "float or array_like of floats, optional",
              "desc": [
                {
                  "__type": "Paragraph",
                  "__tag": 4045,
                  "children": [
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": "Scale, also equals the mode. Must be non-negative. Default is 1."
                    }
                  ]
                }
              ]
            },
            {
              "__type": "DocParam",
              "__tag": 4016,
              "name": "size",
              "annotation": "int or tuple of ints, optional",
              "desc": [
                {
                  "__type": "Paragraph",
                  "__tag": 4045,
                  "children": [
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": "Output shape.  If the given shape is, e.g., "
                    },
                    {
                      "__type": "InlineCode",
                      "__tag": 4051,
                      "value": "(m, n, k)"
                    },
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": ", then "
                    },
                    {
                      "__type": "InlineCode",
                      "__tag": 4051,
                      "value": "m * n * k"
                    },
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": " samples are drawn.  If size is "
                    },
                    {
                      "__type": "InlineCode",
                      "__tag": 4051,
                      "value": "None"
                    },
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": " (default), a single value is returned if "
                    },
                    {
                      "__type": "InlineCode",
                      "__tag": 4051,
                      "value": "scale"
                    },
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": " is a scalar.  Otherwise, "
                    },
                    {
                      "__type": "InlineCode",
                      "__tag": 4051,
                      "value": "np.array(scale).size"
                    },
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": " samples are drawn."
                    }
                  ]
                }
              ]
            }
          ]
        }
      ],
      "title": [],
      "level": 0,
      "target": null
    },
    "Extended Summary": {
      "__type": "Section",
      "__tag": 4015,
      "children": [
        {
          "__type": "Paragraph",
          "__tag": 4045,
          "children": [
            {
              "__type": "Text",
              "__tag": 4046,
              "value": "The "
            },
            {
              "__type": "InlineMath",
              "__tag": 4057,
              "value": "\\chi"
            },
            {
              "__type": "Text",
              "__tag": 4046,
              "value": " and Weibull distributions are generalizations of the Rayleigh."
            }
          ]
        },
        {
          "__type": "Admonition",
          "__tag": 4056,
          "kind": "note",
          "base_type": "note",
          "children": [
            {
              "__type": "AdmonitionTitle",
              "__tag": 4055,
              "children": [
                {
                  "__type": "Text",
                  "__tag": 4046,
                  "value": "note "
                }
              ]
            },
            {
              "__type": "Paragraph",
              "__tag": 4045,
              "children": [
                {
                  "__type": "Text",
                  "__tag": 4046,
                  "value": "New code should use the "
                },
                {
                  "__type": "CrossRef",
                  "__tag": 4002,
                  "value": "rayleigh",
                  "reference": {
                    "__type": "RefInfo",
                    "__tag": 4000,
                    "module": "numpy",
                    "version": "*",
                    "kind": "api",
                    "path": "numpy.random._generator:Generator.rayleigh"
                  },
                  "kind": "module"
                },
                {
                  "__type": "Text",
                  "__tag": 4046,
                  "value": " method of a "
                },
                {
                  "__type": "CrossRef",
                  "__tag": 4002,
                  "value": "Generator",
                  "reference": {
                    "__type": "RefInfo",
                    "__tag": 4000,
                    "module": "numpy",
                    "version": "*",
                    "kind": "api",
                    "path": "numpy.random._generator:Generator"
                  },
                  "kind": "module"
                },
                {
                  "__type": "Text",
                  "__tag": 4046,
                  "value": " instance instead; please see the "
                },
                {
                  "__type": "InlineRole",
                  "__tag": 4003,
                  "value": "random-quick-start",
                  "domain": null,
                  "role": "ref",
                  "inventory": null
                },
                {
                  "__type": "Text",
                  "__tag": 4046,
                  "value": "."
                }
              ]
            }
          ]
        }
      ],
      "title": [],
      "level": 0,
      "target": null
    },
    "Other Parameters": {
      "__type": "Section",
      "__tag": 4015,
      "children": [],
      "title": [],
      "level": 0,
      "target": null
    }
  },
  "_ordered_sections": [
    "Summary",
    "Extended Summary",
    "Parameters",
    "Attributes",
    "Methods",
    "Returns",
    "Yields",
    "Receives",
    "Other Parameters",
    "Raises",
    "Warns",
    "Warnings",
    "Notes"
  ],
  "item_file": null,
  "item_line": null,
  "item_type": "cython_function_or_method",
  "aliases": [
    "numpy.random.rayleigh",
    "numpy.random.RandomState.rayleigh"
  ],
  "example_section_data": {
    "__type": "Section",
    "__tag": 4015,
    "children": [
      {
        "__type": "Text",
        "__tag": 4046,
        "value": "Draw values from the distribution and plot the histogram\n\n"
      },
      {
        "__type": "Code",
        "__tag": 4050,
        "value": "from matplotlib.pyplot import hist\nvalues = hist(np.random.rayleigh(3, 100000), bins=200, density=True)\n",
        "execution_status": "success"
      },
      {
        "__type": "Text",
        "__tag": 4046,
        "value": "\nWave heights tend to follow a Rayleigh distribution. If the mean wave\nheight is 1 meter, what fraction of waves are likely to be larger than 3\nmeters?\n\n"
      },
      {
        "__type": "Code",
        "__tag": 4050,
        "value": "meanvalue = 1\nmodevalue = np.sqrt(2 / np.pi) * meanvalue\ns = np.random.rayleigh(modevalue, 1000000)\n",
        "execution_status": "success"
      },
      {
        "__type": "Text",
        "__tag": 4046,
        "value": "\nThe percentage of waves larger than 3 meters is:\n\n"
      },
      {
        "__type": "Code",
        "__tag": 4050,
        "value": "100.*sum(s>3)/1000000.\n",
        "execution_status": "failure"
      }
    ],
    "title": [],
    "level": 0,
    "target": null
  },
  "see_also": [
    {
      "__type": "SeeAlsoItem",
      "__tag": 4028,
      "name": {
        "__type": "CrossRef",
        "__tag": 4002,
        "value": "random.Generator.rayleigh",
        "reference": {
          "__type": "RefInfo",
          "__tag": 4000,
          "module": "current-module",
          "version": "current-version",
          "kind": "to-resolve",
          "path": "random.Generator.rayleigh"
        },
        "kind": "module"
      },
      "descriptions": [
        {
          "__type": "Paragraph",
          "__tag": 4045,
          "children": [
            {
              "__type": "Text",
              "__tag": 4046,
              "value": "which should be used for new code."
            }
          ]
        }
      ],
      "type": null
    }
  ],
  "signature": {
    "__type": "SignatureNode",
    "__tag": 4029,
    "kind": "function",
    "parameters": [
      {
        "__type": "SigParam",
        "__tag": 4030,
        "name": "scale",
        "annotation": {
          "__type": "Empty",
          "__tag": 4031
        },
        "kind": "POSITIONAL_OR_KEYWORD",
        "default": "1.0"
      },
      {
        "__type": "SigParam",
        "__tag": 4030,
        "name": "size",
        "annotation": {
          "__type": "Empty",
          "__tag": 4031
        },
        "kind": "POSITIONAL_OR_KEYWORD",
        "default": "None"
      }
    ],
    "return_annotation": {
      "__type": "Empty",
      "__tag": 4031
    },
    "target_name": "rayleigh"
  },
  "references": [
    ".. [1] Brighton Webs Ltd., \"Rayleigh Distribution,\"",
    "       https://web.archive.org/web/20090514091424/http://brighton-webs.co.uk:80/distributions/rayleigh.asp",
    ".. [2] Wikipedia, \"Rayleigh distribution\"",
    "       https://en.wikipedia.org/wiki/Rayleigh_distribution"
  ],
  "qa": "numpy.random:RandomState.rayleigh",
  "arbitrary": [],
  "local_refs": [
    "out",
    "scale",
    "size"
  ]
}