groupby_test.py

from collections import defaultdict

from numpy import nan
import numpy as np

from pandas import *

import pandas.lib as tseries
import pandas.core.groupby as gp
import pandas.util.testing as tm
reload(gp)

"""

k = 1000
values = np.random.randn(8 * k)
key1 = np.array(['foo', 'bar', 'baz', 'bar', 'foo', 'baz', 'bar', 'baz'] * k,
                dtype=object)
key2 = np.array(['b', 'b', 'b', 'b', 'a', 'a', 'a', 'a' ] * k,
                dtype=object)
shape, labels, idicts = gp.labelize(key1, key2)

print tseries.group_labels(key1)

# print shape
# print labels
# print idicts

result = tseries.group_aggregate(values, labels, shape)

print tseries.groupby_indices(key2)

df = DataFrame({'key1' : key1,
                'key2' : key2,
                'v1' : values,
                'v2' : values})
k1 = df['key1']
k2 = df['key2']

# del df['key1']
# del df['key2']

# r2 = gp.multi_groupby(df, np.sum, k1, k2)

# print result

gen = gp.generate_groups(df['v1'], labels, shape, axis=1,
                         factory=DataFrame)

res = defaultdict(dict)
for a, gen1 in gen:
    for b, group in gen1:
        print a, b
        print group
        # res[b][a] = group['values'].sum()
        res[b][a] = group.sum()

res = DataFrame(res)

grouped = df.groupby(['key1', 'key2'])
"""

# data = {'A' : [0, 0, 0, 0, 1, 1, 1, 1, 1, 1., nan, nan],
#         'B' : ['A', 'B'] * 6,
#         'C' : np.random.randn(12)}
# df = DataFrame(data)
# df['C'][2:10:2] = nan

# single column
# grouped = df.drop(['B'], axis=1).groupby('A')
# exp = {}
# for cat, group in grouped:
#     exp[cat] = group['C'].sum()
# exp = DataFrame({'C' : exp})
# result = grouped.sum()

# grouped = df.groupby(['A', 'B'])
# expd = {}
# for cat1, cat2, group in grouped:
#     expd.setdefault(cat1, {})[cat2] = group['C'].sum()
# exp = DataFrame(expd).T.stack()
# result = grouped.sum()['C']

# print 'wanted'
# print exp
# print 'got'
# print result

# tm.N = 10000

# mapping = {'A': 0, 'C': 1, 'B': 0, 'D': 1}
# tf = lambda x: x - x.mean()

# df = tm.makeTimeDataFrame()
# ts = df['A']

# # grouped = df.groupby(lambda x: x.strftime('%m/%y'))
# grouped = df.groupby(mapping, axis=1)
# groupedT = df.T.groupby(mapping, axis=0)

# r1 = groupedT.transform(tf).T
# r2 = grouped.transform(tf)

# fillit = lambda x: x.fillna(method='pad')

# f = lambda x: x

# transformed = df.groupby(lambda x: x.strftime('%m/%y')).transform(lambda x: x)

# def ohlc(group):
#     return Series([group[0], group.max(), group.min(), group[-1]],
#                   index=['open', 'high', 'low', 'close'])
# grouper = [lambda x: x.year, lambda x: x.month]
# dr = DateRange('1/1/2000', '1/1/2002')
# ts = Series(np.random.randn(len(dr)), index=dr)

# import string

# k = 20
# n = 1000

# keys = list(string.letters[:k])

# df = DataFrame({'A' : np.tile(keys, n),
#                 'B' : np.repeat(keys[:k/2], n * 2),
#                 'C' : np.random.randn(k * n)})

# def f():
#     for x in df.groupby(['A', 'B']):
#         pass

a = np.arange(100).repeat(100)
b = np.tile(np.arange(100), 100)
index = MultiIndex.from_arrays([a, b])
s = Series(np.random.randn(len(index)), index)
df = DataFrame({'A' : s})
df['B'] = df.index.get_level_values(0)
df['C'] = df.index.get_level_values(1)

def f():
    for x in df.groupby(['B', 'B']):
        pass