Closed
Description
Description
When trying to call preprocessing.scale on a pandas.Series instance, an error is thrown with scikit-learn version 0.20.0. Version 0.19.1. works just fine. The documentation states that the input to preprocessing.scale can be "array-like", and pandas.Series should fulfill this requirement since it is a "one-dimensional ndarray".
Steps/Code to Reproduce
import pandas as pd
from sklearn import preprocessing
s = pd.Series([1.0, 2.0, 3.0])
preprocessing.scale(s)Expected Results
This should be the output (as it is in version 0.19.1):
[-1.22474487, 0. , 1.22474487]
A workaround is replacing preprocessing.scale(s) with preprocessing.scale([i for i in s]), which also yields this output.
Actual Results
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
<ipython-input-16-ef1d298414c3> in <module>
3
4 s = pd.Series([1.0, 2.0, 3.0])
----> 5 preprocessing.scale(s)
~\anaconda3\envs\tensorflow\lib\site-packages\sklearn\preprocessing\data.py in scale(X, axis, with_mean, with_std, copy)
143 X = check_array(X, accept_sparse='csc', copy=copy, ensure_2d=False,
144 warn_on_dtype=True, estimator='the scale function',
--> 145 dtype=FLOAT_DTYPES, force_all_finite='allow-nan')
146 if sparse.issparse(X):
147 if with_mean:
~\anaconda3\envs\tensorflow\lib\site-packages\sklearn\utils\validation.py in check_array(array, accept_sparse, accept_large_sparse, dtype, order, copy, force_all_finite, ensure_2d, allow_nd, ensure_min_samples, ensure_min_features, warn_on_dtype, estimator)
594
595 if (warn_on_dtype and dtypes_orig is not None and
--> 596 {array.dtype} != set(dtypes_orig)):
597 # if there was at the beginning some other types than the final one
598 # (for instance in a DataFrame that can contain several dtypes) then
TypeError: iteration over a 0-d array
Versions
System
------
python: 3.6.7 |Anaconda, Inc.| (default, Oct 28 2018, 19:44:12) [MSC v.1915 64 bit (AMD64)]
executable: C:\Users\...\anaconda3\envs\tensorflow\python.exe
machine: Windows-10-10.0.17134-SP0
Python deps
-----------
pip: 18.1
setuptools: 40.6.2
sklearn: 0.20.0
numpy: 1.15.4
scipy: 1.1.0
Cython: None
pandas: 0.23.4