[BUGFIX] fix the np.error in gensim_vec.W2V.infer_vector

[KenelmQLH]

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Description

(Brief description on what this PR is about)
fix the np.error in gensim_vec.W2V.infer_vector

What does this implement/fix? Explain your changes.

numpy cannot deal with list with different width.
For examples, tokens = [ [ [1,2,..256], [1,2,..,256] ]，[ [1,2,..,256] ] ] , which cannot apply np.mean(tokens, axis = 1)

Pull request type

• [DATASET] Add a new dataset
• [BUGFIX] Bugfix
• [FEATURE] New feature (non-breaking change which adds functionality)
• [BREAKING] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [STYLE] Code style update (formatting, renaming)
• [REFACTOR] Refactoring (no functional changes, no api changes)
• [BUILD] Build related changes
• [DOC] Documentation content changes
• [OTHER] Other (please describe):

Changes

EduNLP/Vector/gensim_vec.py
examples/vectorization/i2v.ipynb
tests/test_vec/test_vec.py

Does this close any currently open issues?

N

Any relevant logs, error output, etc?

the error log in current version:

VisibleDeprecationWarning: Creating an ndarray from ragged nested sequences (which is a list-or-tuple of lists-or-tuples-or ndarrays with different lengths or shapes) is deprecated. If you meant to do this, you must specify 'dtype=object' when creating the ndarray
  return array(a, dtype, copy=False, order=order, subok=True)

AxisError: axis 1 is out of bounds for array of dimension 1

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Comments

• If this change is a backward incompatible change, why must this change be made.
• Interesting edge cases to note here

[tswsxk]

Your example is a list with same width? I cannot get it.

[tswsxk]

The batch items inputted into infer_* are expected to have the same length.