def generate_groups(data, group_index, ngroups, axis=0, factory=lambda x: x):
"""
Parameters
----------
data : BlockManager
Returns
-------
generator
"""
indexer = lib.groupsort_indexer(group_index.astype("i4"), ngroups)[0]
group_index = group_index.take(indexer)
if isinstance(data, BlockManager):
# this is sort of wasteful but...
sorted_axis = data.axes[axis].take(indexer)
sorted_data = data.reindex_axis(sorted_axis, axis=axis)
if isinstance(data, Series):
sorted_axis = data.index.take(indexer)
sorted_data = data.reindex(sorted_axis)
elif isinstance(data, DataFrame):
sorted_data = data.take(indexer, axis=axis)
if isinstance(sorted_data, DataFrame):
def _get_slice(slob):
if axis == 0:
return sorted_data[slob]
else:
return sorted_data.ix[:, slob]
elif isinstance(sorted_data, BlockManager):
def _get_slice(slob):
return factory(sorted_data.get_slice(slob, axis=axis))
elif isinstance(sorted_data, Series):
def _get_slice(slob):
return sorted_data._get_values(slob)
else: # pragma: no cover
def _get_slice(slob):
return sorted_data[slob]
starts, ends = lib.generate_slices(group_index.astype("i4"), ngroups)
for i, (start, end) in enumerate(zip(starts, ends)):
# Since I'm now compressing the group ids, it's now not "possible" to
# produce empty slices because such groups would not be observed in the
# data
assert start < end
yield i, _get_slice(slice(start, end))
def generate_groups(data, label_list, shape, axis=0, factory=lambda x: x):
"""
Parameters
----------
data : BlockManager
Returns
-------
generator
"""
group_index = get_group_index(label_list, shape)
na_mask = np.zeros(len(label_list[0]), dtype=bool)
for arr in label_list:
na_mask |= arr == -1
group_index[na_mask] = -1
indexer = lib.groupsort_indexer(group_index.astype('i4'),
np.prod(shape))[0]
group_index = group_index.take(indexer)
if isinstance(data, BlockManager):
# this is sort of wasteful but...
sorted_axis = data.axes[axis].take(indexer)
sorted_data = data.reindex_axis(sorted_axis, axis=axis)
if isinstance(data, Series):
sorted_axis = data.index.take(indexer)
sorted_data = data.reindex(sorted_axis)
elif isinstance(data, DataFrame):
sorted_data = data.take(indexer, axis=axis)
if isinstance(sorted_data, DataFrame):
def _get_slice(slob):
if axis == 0:
return sorted_data[slob]
else:
return sorted_data.ix[:, slob]
elif isinstance(sorted_data, BlockManager):
def _get_slice(slob):
return factory(sorted_data.get_slice(slob, axis=axis))
elif isinstance(sorted_data, Series):
def _get_slice(slob):
return sorted_data._get_values(slob)
else: # pragma: no cover
def _get_slice(slob):
return sorted_data[slob]
starts, ends = lib.generate_slices(group_index.astype('i4'),
np.prod(shape))
for i, (start, end) in enumerate(zip(starts, ends)):
if start == end:
yield i, None
else:
yield i, _get_slice(slice(start, end))
def generate_groups(data, group_index, ngroups, axis=0, factory=lambda x: x):
"""
Parameters
----------
data : BlockManager
Returns
-------
generator
"""
group_index = com._ensure_int32(group_index)
indexer = lib.groupsort_indexer(group_index, ngroups)[0]
group_index = group_index.take(indexer)
if isinstance(data, BlockManager):
# this is sort of wasteful but...
sorted_axis = data.axes[axis].take(indexer)
sorted_data = data.reindex_axis(sorted_axis, axis=axis)
if isinstance(data, Series):
sorted_axis = data.index.take(indexer)
sorted_data = data.reindex(sorted_axis)
elif isinstance(data, DataFrame):
sorted_data = data.take(indexer, axis=axis)
if isinstance(sorted_data, DataFrame):
def _get_slice(slob):
if axis == 0:
return sorted_data[slob]
else:
return sorted_data.ix[:, slob]
elif isinstance(sorted_data, BlockManager):
def _get_slice(slob):
return factory(sorted_data.get_slice(slob, axis=axis))
elif isinstance(sorted_data, Series):
def _get_slice(slob):
return sorted_data._get_values(slob)
else: # pragma: no cover
def _get_slice(slob):
return sorted_data[slob]
starts, ends = lib.generate_slices(group_index, ngroups)
for i, (start, end) in enumerate(zip(starts, ends)):
# Since I'm now compressing the group ids, it's now not "possible" to
# produce empty slices because such groups would not be observed in the
# data
assert (start < end)
yield i, _get_slice(slice(start, end))
