# Utility functions

## `bw_processing.constants`

This file defines the `*_DTYPE`s used for matrix and
datapackage construction. :

``` python
UNCERTAINTY_DTYPE = [
 ("uncertainty_type", np.uint8),
 ("loc", np.float32),
 ("scale", np.float32),
 ("shape", np.float32),
 ("minimum", np.float32),
 ("maximum", np.float32),
 ("negative", bool),
]
INDICES_DTYPE = [("row", np.int32), ("col", np.int32)]
```

### Creating `numpy` structured arrays

See the API documentation of the [`bw_processing.array_creation` functions](api/bw_processing/array_creation/index).