# mapFun > Invoke a function `n` times and return an array of accumulated function return values.
## Usage ```javascript var mapFun = require( '@stdlib/utils/map-function' ); ``` #### mapFun( fcn, n\[, thisArg ] ) Invokes a function `n` times and returns an `array` of accumulated function return values. ```javascript function fcn( i ) { return i; } var arr = mapFun( fcn, 5 ); // returns [ 0, 1, 2, 3, 4 ] ``` To set the function execution context, provide a `thisArg`. ```javascript function fcn( i ) { this.count += 1; return i; } var context = { 'count': 0 }; var arr = mapFun( fcn, 5, context ); // returns [ 0, 1, 2, 3, 4 ] console.log( context.count ); // => 5 ```
## Notes - The invoked `function` is provided a single argument: the invocation index (zero-based).
## Examples ```javascript var randu = require( '@stdlib/random/base/randu' ); var mapFun = require( '@stdlib/utils/map-function' ); function rand( i ) { return randu() * i * 10.0; } var arr = mapFun( rand, 100 ); console.log( arr ); ```