Create a dataset if it does not already exist

I am trying to create a dataset if it does not exist with the following statement

a=file.get("ds", file.create_dataset("ds", shape=(0, 1), maxshape=(None, 1), data=None,chunks=True))

But I am getting the error RuntimeError: Unable to create link (name already exists) when the dataset ds already exists, which probably means that file.create_dataset("ds", shape=(0, 1), maxshape=(None, 1), data=None,chunks=True) is called when the dataset already exists, even though it should not be called. A workaround would be to

a=file.get("ds")
if a is None:
    a=file.create_dataset("ds", shape=(0, 1), maxshape=(None, 1), data=None,chunks=True)

However, it seems like file.get should handle this situation.

Here are my specifications

• Operating System: Mac OS Mojave (10.14.6)
• Python version: 2.7.15+
• Where Python was acquired: system Python
• h5py version: 2.7.1 (h5py.__version__)
• hdf5 version: 1.10.0
• The full traceback/stack trace shown (if it appears)

Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/usr/lib/python2.7/dist-packages/h5py/_hl/group.py", line 109, in create_dataset
    self[name] = dset
  File "/usr/lib/python2.7/dist-packages/h5py/_hl/group.py", line 277, in __setitem__
    h5o.link(obj.id, self.id, name, lcpl=lcpl, lapl=self._lapl)
  File "h5py/_objects.pyx", line 54, in h5py._objects.with_phil.wrapper (/build/h5py-qzs83i/h5py-2.7.1/h5py/_objects.c:2847)
  File "h5py/_objects.pyx", line 55, in h5py._objects.with_phil.wrapper (/build/h5py-qzs83i/h5py-2.7.1/h5py/_objects.c:2805)
  File "h5py/h5o.pyx", line 202, in h5py.h5o.link (/build/h5py-qzs83i/h5py-2.7.1/h5py/h5o.c:3899)
RuntimeError: Unable to create link (name already exists)

[takluyver]

My previous comment was meant to be a polite way of saying: please work it out yourself.

[AbdulKaderJaleel]

here is the sample code:

with h5py.File(‘filtered.h5’, ‘a’) as f: # Create a group called data print(f.keys()) if f.keys()== None: g = f.create_group(‘data’) g.create_dataset(filename, data=norm_image) else: g = f.require_group(‘data’) g.create_dataset(filename, data=norm_image)