def _get_row_major(self, df, row_tuple):
valid_indices = self._compute_validity_mask(df, row_tuple)
from cudf import Series
result = df.take(Series(valid_indices))
# Build new index - INDEX based MultiIndex
# ---------------
from cudf import DataFrame
out_index = DataFrame()
# Select the last n-k columns where n is the number of source
# levels and k is the length of the indexing tuple
for k in range(len(row_tuple), len(df.index.levels)):
out_index.add_column(df.index.names[k],
df.index.codes[df.index.codes.columns[k]])
# If there's only one column remaining in the output index, convert
# it into a StringIndex and name the final index values according
# to the proper codes.
if len(out_index.columns) == 1:
out_index = []
for val in result.index.codes[result.index.codes.columns[len(result.index.codes.columns)-1]]: # noqa: E501
out_index.append(result.index.levels[
len(result.index.codes.columns)-1][val])
# TODO: Warning! The final index column could be arbitrarily
# ordered integers, not Strings, so we need to check for that
# dtype and produce a GenericIndex instead of a StringIndex
out_index = StringIndex(out_index)
out_index.name = result.index.names[len(result.index.names)-1]
result.index = out_index
else:
# Otherwise pop the leftmost levels, names, and codes from the
# source index until it has the correct number of columns (n-k)
if(len(out_index.columns)) > 0:
result.reset_index(drop=True)
result.index = result.index._popn(len(row_tuple))
return result
def _index_and_downcast(self, result, index, index_key):
from cudf import DataFrame
from cudf import Series
if isinstance(index_key, (numbers.Number, slice)):
index_key = [index_key]
if (
len(index_key) > 0 and not isinstance(index_key, tuple)
) or isinstance(index_key[0], slice):
index_key = index_key[0]
slice_access = False
if isinstance(index_key, slice):
slice_access = True
out_index = DataFrame()
# Select the last n-k columns where n is the number of _source_data
# columns and k is the length of the indexing tuple
size = 0
if not isinstance(index_key, (numbers.Number, slice)):
size = len(index_key)
for k in range(size, len(index._source_data.columns)):
if index.names is None:
name = k
else:
name = index.names[k]
out_index.add_column(
name, index._source_data[index._source_data.columns[k]]
)
if len(result) == 1 and size == 0 and slice_access is False:
# If the final result is one row and it was not mapped into
# directly, return a Series with a tuple as name.
result = result.T
result = result[result.columns[0]]
elif len(result) == 0 and slice_access is False:
# Pandas returns an empty Series with a tuple as name
# the one expected result column
series_name = []
for idx, code in enumerate(index._source_data.columns):
series_name.append(index._source_data[code][0])
result = Series([])
result.name = tuple(series_name)
elif len(out_index.columns) == 1:
# If there's only one column remaining in the output index, convert
# it into an Index and name the final index values according
# to the _source_data column names
last_column = index._source_data.columns[-1]
out_index = index._source_data[last_column]
out_index = as_index(out_index)
out_index.name = index.names[len(index.names) - 1]
index = out_index
elif len(out_index.columns) > 1:
# Otherwise pop the leftmost levels, names, and codes from the
# source index until it has the correct number of columns (n-k)
result.reset_index(drop=True)
index = index._popn(size)
if isinstance(index_key, tuple):
result = result.set_index(index)
return result
def _popn(self, n):
""" Returns a copy of this index without the left-most n values.
Removes n names, labels, and codes in order to build a new index
for results.
"""
from cudf import DataFrame
codes = DataFrame()
for idx in self.codes.columns[n:]:
codes.add_column(idx, self.codes[idx])
result = MultiIndex(self.levels[n:], codes)
result.names = self.names[n:]
return result
def _get_row_major(self, df, row_tuple):
slice_access = False
if isinstance(row_tuple[0], numbers.Number):
valid_indices = row_tuple[0]
elif isinstance(row_tuple[0], slice):
# 1. empty slice compute
if row_tuple[0].stop == 0:
valid_indices = []
else:
slice_access = True
start = row_tuple[0].start or 0
stop = row_tuple[0].stop or len(df)
step = row_tuple[0].step or 1
valid_indices = cudautils.arange(start, stop, step)
else:
valid_indices = self._compute_validity_mask(df, row_tuple)
from cudf import Series
result = df.take(Series(valid_indices))
# Build new index - INDEX based MultiIndex
# ---------------
from cudf import DataFrame
out_index = DataFrame()
# Select the last n-k columns where n is the number of source
# levels and k is the length of the indexing tuple
size = 0
if not isinstance(row_tuple[0], (numbers.Number, slice)):
size = len(row_tuple)
for k in range(size, len(df.index.levels)):
out_index.add_column(df.index.names[k],
df.index.codes[df.index.codes.columns[k]])
# If there's only one column remaining in the output index, convert
# it into an Index and name the final index values according
# to the proper codes.
if len(out_index.columns) == 1:
out_index = []
for val in result.index.codes[result.index.codes.columns[len(result.index.codes.columns)-1]]: # noqa: E501
out_index.append(result.index.levels[
len(result.index.codes.columns)-1][val])
out_index = as_index(out_index)
out_index.name = result.index.names[len(result.index.names)-1]
result.index = out_index
else:
if len(result) == 1 and size == 0 and slice_access is False:
# If the final result is one row and it was not mapped into
# directly
result = result.T
result = result[result.columns[0]]
# convert to Series
series_name = []
for idx, code in enumerate(result.columns.codes):
series_name.append(result.columns.levels[idx][
result.columns.codes[code][0]])
result = Series(list(result._cols.values())[0],
name=series_name)
result.name = tuple(series_name)
elif(len(out_index.columns)) > 0:
# Otherwise pop the leftmost levels, names, and codes from the
# source index until it has the correct number of columns (n-k)
result.reset_index(drop=True)
result.index = result.index._popn(size)
return result
