Python – Deleting hdf5 dataset using h5py

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Is there any way to remove a dataset from an hdf5 file, preferably using h5py? Or alternatively, is it possible to overwrite a dataset while keeping the other datasets intact?

To my understanding, h5py can read/write hdf5 files in 5 modes

f = h5py.File("filename.hdf5",'mode')

where mode can be rfor read, r+ for read-write, a for read-write but creates a new file if it doesn't exist, w for write/overwrite, and w- which is same as w but fails if file already exists. I have tried all but none seem to work.

Any suggestions are much appreciated.

Best Answer

Yes, this can be done.

with h5py.File(input,  "a") as f:
    del f[datasetname]

You will need to have the file open in a writeable mode, for example append (as above) or write.

As noted by @seppo-enarvi in the comments the purpose of the previously recommended f.__delitem__(datasetname) function is to implement the del operator, so that one can delete a dataset using del f[datasetname]

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will simply loop over the keys in the dictionary, rather than the keys and values. To loop over both key and value you can use the following:

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For Python 2.x:

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Best Answer

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