# setProps
> Define non-enumerable read-only properties which expose ndarray function meta data.
## Usage
```javascript
var setProps = require( '@stdlib/ndarray/base/meta-data-props' );
```
#### setProps( meta, dtypes, obj )
Defines non-enumerable read-only properties which expose ndarray function meta data.
```javascript
// Define ndarray function meta data:
var meta = {
'nargs': 2,
'nin': 1,
'nout': 1
};
// Define the list of ndarray data types:
var dtypes = [
'float64', 'float64'
];
// Define an object/function on which to set the properties:
var obj = {};
// Set the properties:
setProps( meta, dtypes, obj );
```
The `meta` data argument should be an object with the following properties:
- **nargs**: total number of arguments. This value is one more than might be expected, as the output array is treated as an implicit argument, even when not explicitly provided.
- **nin**: number of input ndarrays.
- **nout**: number of output ndarrays.
## Examples
```javascript
var setProps = require( '@stdlib/ndarray/base/meta-data-props' );
// Define ndarray function meta data:
var meta = {
'nargs': 2,
'nin': 1,
'nout': 1
};
// Define the list of ndarray data types:
var types = [
'float64', 'float64',
'float32', 'float32',
'generic', 'generic'
];
// Define an object/function on which to set the properties:
var obj = {};
// Set the properties:
setProps( meta, types, obj );
// Retrieve ndarray function data...
var nargs = obj.nargs;
// returns 2
var nin = obj.nin;
// returns 1
var nout = obj.nout;
// returns 1
var sigs = obj.types;
// returns [...]
```