Setting index name / names for Series

[itholic]

Unlike pandas, koalas.Series can't set the index name like below.

>>> pser = pd.Series([1, 2, 3, 4, 5])
>>> pser.index.name = 'koalas'
>>> pser.index.name
'koalas'

>>> kser = ks.Series([1, 2, 3, 4, 5])
>>> kser.index.name = 'koalas'
>>> kser.index.name

For MultiIndex also

>>> midx = pd.MultiIndex([['lama', 'cow', 'falcon'],
...                       ['speed', 'weight', 'length']],
...                      [[0, 0, 0, 1, 1, 1, 2, 2, 2],
...                       [0, 1, 2, 0, 1, 2, 0, 1, 2]])
>>> pser = pd.Series([45, 200, 1.2, 30, 250, 1.5, 320, 1, 0.3], index=midx)
>>> pser.index.names
FrozenList([None, None])
>>> pser.index.names = ['hello', 'koalas']
>>> pser.index.names
FrozenList(['hello', 'koalas'])

>>> midx = pd.MultiIndex([['lama', 'cow', 'falcon'],
...                       ['speed', 'weight', 'length']],
...                      [[0, 0, 0, 1, 1, 1, 2, 2, 2],
...                       [0, 1, 2, 0, 1, 2, 0, 1, 2]])
>>> kser = ks.Series([45, 200, 1.2, 30, 250, 1.5, 320, 1, 0.3], index=midx)
>>> kser.index.names
[None, None]
>>> kser.index.names = ['hello', 'koalas']
>>> kser.index.names
[None, None]

So, this PR suggests that make ours possible also.

>>> kser = ks.Series([1, 2, 3, 4, 5])
>>> kser.index.name = 'koalas'
>>> kser.index.name
'koalas'

>>> midx = pd.MultiIndex([['lama', 'cow', 'falcon'],
...                       ['speed', 'weight', 'length']],
...                      [[0, 0, 0, 1, 1, 1, 2, 2, 2],
...                       [0, 1, 2, 0, 1, 2, 0, 1, 2]])
>>> kser = ks.Series([45, 200, 1.2, 30, 250, 1.5, 320, 1, 0.3], index=midx)
>>> kser.index.names
[None, None]
>>> kser.index.names = ['hello', 'koalas']
>>> kser.index.names
['hello', 'koalas']

[codecov-io]

Codecov Report

Merging #1079 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master    #1079   +/-   ##
=======================================
  Coverage   95.14%   95.14%           
=======================================
  Files          35       35           
  Lines        6958     6958           
=======================================
  Hits         6620     6620           
  Misses        338      338

Impacted Files	Coverage Δ
databricks/koalas/series.py	96.5% <100%> (ø)	⬆️

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[HyukjinKwon]

+1

[HyukjinKwon]

Looks good otherwise.

[softagram-bot]

Softagram Impact Report for pull/1079 (head commit: 8b6204c)

⚠️ Copy paste found

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 302, 319:

                     pd.Series([True, False], name='x'),
                     pd.Series([0, 1], name='x'),
                     pd.Series([1, 2,...(truncated 330 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 746, 887:

        midx = pd.MultiIndex([['lama', 'cow', 'falcon'],
                              ['speed', 'weight', 'length']],
                             [[0, 0, 0, 1, 1, 1, 2, 2, 2]...(truncated 280 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 747, 888, 924:

                              ['speed', 'weight', 'length']],
                             [[0, 0, 0, 1, 1, 1, 2, 2, 2],
                      ...(truncated 256 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 718, 921:

        # For MultiIndex
        midx = pd.MultiIndex([['lama', 'cow', 'falcon'],
                              ['speed', 'weight', 'length']],
                             [[...(truncated 167 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 721, 747, 888:

                              ['speed', 'weight', 'length']],
                             [[0, 0, 0, 1, 1, 1, 2, 2, 2],
                      ...(truncated 117 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 170, 180:

        pdf = pd.DataFrame({
            'left':  [True, False, True, False, np.nan, np.nan, True, False, np.nan],
            'right': [True, False, False, True, True, False, n...(truncated 119 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 749, 790, 890, 926:

                              [0, 1, 2, 0, 1, 2, 0, 1, 2]])
        kser = ks.Series([45, 200, 1.2, 30, 250, 1.5, 320, 1, 0.3],
             ...(truncated 137 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 914, 934:

        self.assert_eq(kser.pct_change(periods=-1),
                       pser.pct_change(periods=-1), almost=True)
        self.assert_eq(kser.pct_change(periods=-10...(truncated 213 chars)

ℹ️ test_series.py: Copy paste fragment inside the same file on lines 639, 664:

        index = pd.MultiIndex.from_arrays([
            ['a', 'a', 'b', 'b'], ['c', 'd', 'e', 'f']], names=('first', 'se...(truncated 151 chars)

ℹ️ series.py: Copy paste fragment on line 1248 shared with ../frame.py:

    def to_latex(self, buf=None, columns=None, col_space=None, header=True, index=True,
                 na_rep='NaN',...(truncated 256 chars)

ℹ️ series.py: Copy paste fragment inside the same file on lines 3105, 3213:

        results = sdf.select([scol] + index_scols).take(1)
        if len(results) == 0:
           ...(truncated 409 chars)

ℹ️ series.py: Copy paste fragment inside the same file on lines 4124, 4346:

        sdf = self._internal.sdf \
            .select(cols) \
            .where(reduce(lambda x, y: x & y, rows))

        if len(self._inter...(truncated 255 chars)

Now that you are on the file, it would be easier to pay back some tech. debt.

⭐ Change Overview

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💡 Insights

• Co-change Alert: You modified series.py. Often frame.py (databricks/koalas) is modified at the same time.

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• Permalink: Full report for pull/1079

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