[ SciPy v1.12.0 Manual  ](../../index.html)

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1.12.0

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  * ` whosmat  `

#  scipy.io.whosmat  #

scipy.io.  whosmat  (  _ file_name  _ , _ appendmat  =  True  _ , _ **  kwargs
_ )  [ [source]
](https://github.com/scipy/scipy/blob/v1.12.0/scipy/io/matlab/_mio.py#L304-L359)
#

    

List variables inside a MATLAB file.

Parameters  :

    

**file_name** str

    

Name of the mat file (do not need .mat extension if appendmat==True) Can also
pass open file-like object.

**appendmat** bool, optional

    

True to append the .mat extension to the end of the given filename, if not
already present. Default is True.

**byte_order** str or None, optional

    

None by default, implying byte order guessed from mat file. Otherwise can be
one of (ânativeâ, â=â, âlittleâ, â<â, âBIGâ, â>â).

**mat_dtype** bool, optional

    

If True, return arrays in same dtype as would be loaded into MATLAB (instead
of the dtype with which they are saved).

**squeeze_me** bool, optional

    

Whether to squeeze unit matrix dimensions or not.

**chars_as_strings** bool, optional

    

Whether to convert char arrays to string arrays.

**matlab_compatible** bool, optional

    

Returns matrices as would be loaded by MATLAB (implies squeeze_me=False,
chars_as_strings=False, mat_dtype=True, struct_as_record=True).

**struct_as_record** bool, optional

    

Whether to load MATLAB structs as NumPy record arrays, or as old-style NumPy
arrays with dtype=object. Setting this flag to False replicates the behavior
of SciPy version 0.7.x (returning numpy object arrays). The default setting is
True, because it allows easier round-trip load and save of MATLAB files.

Returns  :

    

**variables** list of tuples

    

A list of tuples, where each tuple holds the matrix name (a string), its shape
(tuple of ints), and its data class (a string). Possible data classes are:
int8, uint8, int16, uint16, int32, uint32, int64, uint64, single, double,
cell, struct, object, char, sparse, function, opaque, logical, unknown.

Notes

v4 (Level 1.0), v6 and v7 to 7.2 matfiles are supported.

You will need an HDF5 python library to read matlab 7.3 format mat files (e.g.
h5py). Because SciPy does not supply one, we do not implement the HDF5 / 7.3
interface here.

New in version 0.12.0.

Examples

    
    
    >>> from io import BytesIO
    >>> import numpy as np
    >>> from scipy.io import savemat, whosmat
    

Create some arrays, and use [ ` savemat  `
](scipy.io.savemat.html#scipy.io.savemat "scipy.io.savemat") to write them to
a ` BytesIO  ` instance.

    
    
    >>> a = np.array([[10, 20, 30], [11, 21, 31]], dtype=np.int32)
    >>> b = np.geomspace(1, 10, 5)
    >>> f = BytesIO()
    >>> savemat(f, {'a': a, 'b': b})
    

Use  ` whosmat  ` to inspect ` f  ` . Each tuple in the output list gives the
name, shape and data type