# core.eval:loadmatrix()


Open matrix ascii data as well as hdf5 files generated by matrix.


Usage

``` python
core.eval:loadmatrix(
    filename,
    structured=True,
    print_header=False,
    replace_None=False,
    *,
    to_polars=False,
)
```


Returns all header information as well as data as numpy.ndarray. Data fields should be addressed by column name (structured=True, default) or by index (structured=False).


## Parameters


`filename: str or pathlib.Path`  
path to file

`structured: bool = ``True`  
controls whether a structured or a plain numpy array is returned

`print_header: bool = ``False`  
if true, prints the column names read from the file together with their index

`replace_None: boolean = ``False`  
%deprecated: raises a NotImplementedError.

`to_polars: bool = ``False`  
if true, the data of text files is returned as a native polars DataFrame instead of numpy. This option is not supported for HDF5 files and raises NotImplementedError.


## Returns


`header: HeaderDict`  
Dictionary containing the header information with core typed fields

`data: np.ndarray | pl.DataFrame | dict[str, np.ndarray]`  
Data array, polars DataFrame, or dict for unequal length arrays


## Warns


`FutureWarning`  
If a text file is loaded without `to_polars=True`, as the numpy return is deprecated and will be removed in a future release.