Question: I have .mat files with HDF5 data and I want to load it into Python (Pandas DataFrame). I can load the file:

```
f2 = h5py.File("file.mat")
f2['data']

```

which is an HDF5 dataset:

`<HDF5 dataset "data": shape (9999999, 32), type "<f8">`

If I read it with Pandas:

```
g = pd.read_hdf("file.mat",'data')

```

I get the following error:

`cannot create a storer if the object is not existing nor a value are passed`

How do I convert this to a Pandas DataFrame?

Answer: 
AFAIK you can't read HDF5 files using Pandas methods, that have NOT been written using Pandas.

You can read them using one of the following approaches:

[read matlab v7.3 file into python list of numpy arrays via h5py](https://stackoverflow.com/questions/27670149/read-matlab-v7-3-file-into-python-list-of-numpy-arrays-via-h5py)

[Reading ALL variables in a .mat file with python h5py](https://stackoverflow.com/questions/29852481/reading-all-variables-in-a-mat-file-with-python-h5py)

<http://poquitopicante.blogspot.de/2014/05/loading-matlab-mat-file-into-pandas.html>

[Read .mat files in Python](https://stackoverflow.com/questions/874461/read-mat-files-in-python)
In the first example your file is `"file.mat"` and in the second `"data.mat"`