# iterMap
> Create an [iterator][mdn-iterator-protocol] which invokes a unary function accepting a single numeric argument for each iterated value.
## Usage
```javascript
var iterMap = require( '@stdlib/math/iter/tools/map' );
```
#### iterMap( iterator, fcn\[, options] )
Returns an [iterator][mdn-iterator-protocol] which invokes a unary `function` accepting a single numeric argument for each iterated value.
```javascript
var array2iterator = require( '@stdlib/array/to-iterator' );
var sin = require( '@stdlib/math/base/special/sin' );
var it = iterMap( array2iterator( [ 1, 2, 3, 4 ] ), sin );
// returns
## Notes
- If an environment supports `Symbol.iterator` **and** a provided [iterator][mdn-iterator-protocol] is iterable, the returned [iterator][mdn-iterator-protocol] is iterable.
## Examples
```javascript
var randu = require( '@stdlib/random/iter/randu' );
var sin = require( '@stdlib/math/base/special/sin' );
var iterMap = require( '@stdlib/math/iter/tools/map' );
// Create a seeded iterator for generating pseudorandom numbers:
var rand = randu({
'seed': 1234,
'iter': 10
});
// Create an iterator which consumes the pseudorandom number iterator:
var it = iterMap( rand, sin );
// Perform manual iteration...
var r;
while ( true ) {
r = it.next();
if ( r.done ) {
break;
}
console.log( r.value );
}
```
[mdn-iterator-protocol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols#The_iterator_protocol