Version: 2020.3
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Random.Range

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Declaration

public static float Range(float minInclusive, float maxInclusive);

Description

Returns a random float within [minInclusive..maxInclusive] (range is inclusive).

If minInclusive is greater than maxInclusive, then the numbers are automatically swapped.

Important: Both the lower and upper bounds are inclusive. Any given float value between them, including both minInclusive and maxInclusive, will appear on average approximately once every ten million random samples.

There is an int overload of this function that operates slightly differently, especially regarding the range maximum. See its docs below.

See Random for details on the algorithm, and for examples of how UnityEngine.Random may be different from other random number generators.

using UnityEngine;

public class ExampleClass : MonoBehaviour { public GameObject prefab;

// Click the "Instantiate!" button and a new `prefab` will be instantiated // somewhere within -10.0 and 10.0 (inclusive) on the x-z plane void OnGUI() { if (GUI.Button(new Rect(10, 10, 100, 50), "Instantiate!")) { var position = new Vector3(Random.Range(-10.0f, 10.0f), 0, Random.Range(-10.0f, 10.0f)); Instantiate(prefab, position, Quaternion.identity); } } }

Declaration

public static int Range(int minInclusive, int maxExclusive);

Description

Return a random int within [minInclusive..maxExclusive) (Read Only).

This method will behave in the following ways:

  • maxExcusive is exclusive, so for example Random.Range(0, 10) will return a value between 0 and 9, each with approximately equal probability.
  • If minInclusive and maxExclusive are equal, then the "exclusive rule" is ignored and minInclusive will be returned.
  • If minInclusive is greater than maxExclusive, then the numbers are automatically swapped.

There is a float overload of this function that operates slightly differently, especially regarding the range maximum. See its docs above.

See Random for details on the algorithm, and for examples of how UnityEngine.Random may be different from other random number generators.

using UnityEngine;

public class ExampleClass : MonoBehaviour { public GameObject prefab; public float zoffset = 10;

// Click the "Instantiate!" button and a new grid of `prefab` objects will be // instantiated with a random number of items in each direction. void OnGUI() { if (GUI.Button(new Rect(10, 10, 100, 50), "Instantiate!")) { // the grid will always be 1, 2, 3, 4, or 5 prefabs wide int xcount = Random.Range(1, 6); // the grid will always be 2, 3, or 4 prefabs long int ycount = Random.Range(2, 5);

for (int x = 0; x != xcount; ++x) { for (int y = 0; y != ycount; ++y) { var position = new Vector3(x * 2, zoffset, y * 2); Instantiate(prefab, position, Quaternion.identity); } }

zoffset += 2; } } }