# cdfZipf {#cdfzipf}

**Parent topic:**[Functions](../../Functions/category.md)

## Syntax {#syntax}

`cdfZipf(num, exponent, X)`

## Arguments {#arguments}

**num** is a positive integer.

**exponent** is a non-negative floating number.

**X** is a numeric scalar or vector.

## Details {#details}

Return the value of the cumulative distribution function of a Zipfian distribution.

## Examples {#examples}

```
cdfZipf(10, 0.5, [1, 3, 5, 7, 9]);
// output: [0.199164, 0.454981, 0.643631, 0.800216, 0.937019]
```

