ENH: Finish adding groupby to rank/top/bottom.

- Added test coverage for grouped and masked top/bottom.

- Added test coverage for grouped rank on datetime factors.

- Fixed an issue where grouped rank would fail on datetime inputs
  because unary-negative isn't defined for datetimes.  We now instead
  directly invoke a function from rank.pyx that does the normalizations
  as neeeded.

- Fixed an issue where GroupedRowTransform assumed that it produced the
  same dtype as its input.  This isn't true for rank() of a
  datetime-dtype factor.  GroupedRowTransform now takes a required dtype
  parameter.

- Similarly, fixed an issue where GroupedRowTransform assumed that its
  missing_value was the same as its parent's, which isn't true for
  rank() of a datetime-dtype factor.  GroupedRowTransform now takes a
  required dtype parameter.

- Fixed an issue where Factor.demean() and Factor.zscore() weren't
  properly cached because their static_identity included a closure that
  was dynamically generated on each invocation.  They both now always
  use a function defined at module scope.
This commit is contained in:
Scott Sanderson
2016-07-26 01:56:50 -04:00
parent 9e3404646e
commit 49bb8264dc
6 changed files with 332 additions and 44 deletions
+4 -7
View File
@@ -336,7 +336,8 @@ class FactorTestCase(BasePipelineTestCase):
for method in results:
check_arrays(expected[method], results[method])
def test_grouped_rank_ascending(self, factor_dtype=float64_dtype):
@for_each_factor_dtype
def test_grouped_rank_ascending(self, name, factor_dtype=float64_dtype):
f = F(dtype=factor_dtype)
c = C()
@@ -439,7 +440,8 @@ class FactorTestCase(BasePipelineTestCase):
check({'ordinal': f.rank(groupby=c, ascending=True)})
check({'ordinal': f.rank(groupby=str_c, ascending=True)})
def test_grouped_rank_descending(self, factor_dtype=float64_dtype):
@for_each_factor_dtype
def test_grouped_rank_descending(self, name, factor_dtype):
f = F(dtype=factor_dtype)
c = C()
@@ -532,11 +534,6 @@ class FactorTestCase(BasePipelineTestCase):
check({'ordinal': f.rank(groupby=c, ascending=False)})
check({'ordinal': f.rank(groupby=str_c, ascending=False)})
# TODO finish this
# @for_each_factor_dtype
# def test_grouped_rank_after_mask(self, name, factor_dtype):
# pass
@parameterized.expand([
# Test cases computed by doing:
# from numpy.random import seed, randn
+252 -2
View File
@@ -1,9 +1,11 @@
"""
Tests for filter terms.
"""
from functools import partial
from itertools import product
from operator import and_
from toolz import compose
from numpy import (
arange,
argsort,
@@ -19,15 +21,17 @@ from numpy import (
ones,
ones_like,
putmask,
rot90,
sum as np_sum
)
from numpy.random import randn, seed as random_seed
from zipline.errors import BadPercentileBounds
from zipline.pipeline import Filter, Factor, TermGraph
from zipline.pipeline.classifiers import Classifier
from zipline.pipeline.factors import CustomFactor
from zipline.testing import check_arrays, parameter_space
from zipline.utils.numpy_utils import float64_dtype
from zipline.testing import check_arrays, parameter_space, permute_rows
from zipline.utils.numpy_utils import float64_dtype, int64_dtype
from .base import BasePipelineTestCase, with_default_shape
@@ -71,6 +75,13 @@ class SomeOtherFactor(Factor):
window_length = 0
class SomeClassifier(Classifier):
dtype = int64_dtype
inputs = ()
window_length = 0
missing_value = -1
class Mask(Filter):
inputs = ()
window_length = 0
@@ -82,6 +93,7 @@ class FilterTestCase(BasePipelineTestCase):
super(FilterTestCase, self).init_instance_fixtures()
self.f = SomeFactor()
self.g = SomeOtherFactor()
self.c = SomeClassifier()
@with_default_shape
def randn_data(self, seed, shape):
@@ -415,3 +427,241 @@ class FilterTestCase(BasePipelineTestCase):
results['windowsafe'],
full(output_shape, factor_len, dtype=float64)
)
@parameter_space(
dtype=('float64', 'datetime64[ns]'),
seed=(1, 2, 3),
__fail_fast=True
)
def test_top_with_groupby(self, dtype, seed):
permute = partial(permute_rows, seed)
permuted_array = compose(permute, partial(array, dtype=int64_dtype))
shape = (8, 8)
# Shuffle the input rows to verify that we correctly pick out the top
# values independently of order.
factor_data = permute(arange(0, 64, dtype=dtype).reshape(shape))
classifier_data = permuted_array([[0, 0, 1, 1, 2, 2, 0, 0],
[0, 0, 1, 1, 2, 2, 0, 0],
[0, 1, 2, 3, 0, 1, 2, 3],
[0, 1, 2, 3, 0, 1, 2, 3],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0]])
f = self.f
c = self.c
self.check_terms(
terms={
'1': f.top(1, groupby=c),
'2': f.top(2, groupby=c),
'3': f.top(3, groupby=c),
},
initial_workspace={
f: factor_data,
c: classifier_data,
},
expected={
# Should be the rightmost location of each entry in
# classifier_data.
'1': permuted_array([[0, 0, 0, 1, 0, 1, 0, 1],
[0, 0, 0, 1, 0, 1, 0, 1],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 1, 0, 0, 0, 1],
[0, 0, 0, 1, 0, 0, 0, 1],
[0, 0, 0, 0, 0, 0, 0, 1],
[0, 0, 0, 0, 0, 0, 0, 1]], dtype=bool),
# Should be the first and second-rightmost location of each
# entry in classifier_data.
'2': permuted_array([[0, 0, 1, 1, 1, 1, 1, 1],
[0, 0, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[0, 0, 1, 1, 0, 0, 1, 1],
[0, 0, 1, 1, 0, 0, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1]], dtype=bool),
# Should be the first, second, and third-rightmost location of
# each entry in classifier_data.
'3': permuted_array([[0, 1, 1, 1, 1, 1, 1, 1],
[0, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[0, 1, 1, 1, 0, 1, 1, 1],
[0, 1, 1, 1, 0, 1, 1, 1],
[0, 0, 0, 0, 0, 1, 1, 1],
[0, 0, 0, 0, 0, 1, 1, 1]], dtype=bool),
},
mask=self.build_mask(self.ones_mask(shape=shape)),
)
@parameter_space(
dtype=('float64', 'datetime64[ns]'),
seed=(1, 2, 3),
__fail_fast=True
)
def test_top_and_bottom_with_groupby(self, dtype, seed):
permute = partial(permute_rows, seed)
permuted_array = compose(permute, partial(array, dtype=int64_dtype))
shape = (8, 8)
# Shuffle the input rows to verify that we correctly pick out the top
# values independently of order.
factor_data = permute(arange(0, 64, dtype=dtype).reshape(shape))
classifier_data = permuted_array([[0, 0, 1, 1, 2, 2, 0, 0],
[0, 0, 1, 1, 2, 2, 0, 0],
[0, 1, 2, 3, 0, 1, 2, 3],
[0, 1, 2, 3, 0, 1, 2, 3],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0]])
f = self.f
c = self.c
self.check_terms(
terms={
'top1': f.top(1, groupby=c),
'top2': f.top(2, groupby=c),
'top3': f.top(3, groupby=c),
'bottom1': f.bottom(1, groupby=c),
'bottom2': f.bottom(2, groupby=c),
'bottom3': f.bottom(3, groupby=c),
},
initial_workspace={
f: factor_data,
c: classifier_data,
},
expected={
# Should be the rightmost location of each entry in
# classifier_data.
'top1': permuted_array([[0, 0, 0, 1, 0, 1, 0, 1],
[0, 0, 0, 1, 0, 1, 0, 1],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 1, 0, 0, 0, 1],
[0, 0, 0, 1, 0, 0, 0, 1],
[0, 0, 0, 0, 0, 0, 0, 1],
[0, 0, 0, 0, 0, 0, 0, 1]], dtype=bool),
# Should be the leftmost location of each entry in
# classifier_data.
'bottom1': permuted_array([[1, 0, 1, 0, 1, 0, 0, 0],
[1, 0, 1, 0, 1, 0, 0, 0],
[1, 1, 1, 1, 0, 0, 0, 0],
[1, 1, 1, 1, 0, 0, 0, 0],
[1, 0, 0, 0, 1, 0, 0, 0],
[1, 0, 0, 0, 1, 0, 0, 0],
[1, 0, 0, 0, 0, 0, 0, 0],
[1, 0, 0, 0, 0, 0, 0, 0]],
dtype=bool),
# Should be the first and second-rightmost location of each
# entry in classifier_data.
'top2': permuted_array([[0, 0, 1, 1, 1, 1, 1, 1],
[0, 0, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[0, 0, 1, 1, 0, 0, 1, 1],
[0, 0, 1, 1, 0, 0, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1]], dtype=bool),
# Should be the first and second leftmost location of each
# entry in classifier_data.
'bottom2': permuted_array([[1, 1, 1, 1, 1, 1, 0, 0],
[1, 1, 1, 1, 1, 1, 0, 0],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 0, 0, 1, 1, 0, 0],
[1, 1, 0, 0, 1, 1, 0, 0],
[1, 1, 0, 0, 0, 0, 0, 0],
[1, 1, 0, 0, 0, 0, 0, 0]],
dtype=bool),
# Should be the first, second, and third-rightmost location of
# each entry in classifier_data.
'top3': permuted_array([[0, 1, 1, 1, 1, 1, 1, 1],
[0, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[0, 1, 1, 1, 0, 1, 1, 1],
[0, 1, 1, 1, 0, 1, 1, 1],
[0, 0, 0, 0, 0, 1, 1, 1],
[0, 0, 0, 0, 0, 1, 1, 1]], dtype=bool),
# Should be the first, second, and third-leftmost location of
# each entry in classifier_data.
'bottom3': permuted_array([[1, 1, 1, 1, 1, 1, 1, 0],
[1, 1, 1, 1, 1, 1, 1, 0],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 1, 1, 1, 1, 1],
[1, 1, 1, 0, 1, 1, 1, 0],
[1, 1, 1, 0, 1, 1, 1, 0],
[1, 1, 1, 0, 0, 0, 0, 0],
[1, 1, 1, 0, 0, 0, 0, 0]],
dtype=bool),
},
mask=self.build_mask(self.ones_mask(shape=shape)),
)
@parameter_space(
dtype=('float64', 'datetime64[ns]'),
seed=(1, 2, 3),
__fail_fast=True,
)
def test_top_and_bottom_with_groupby_and_mask(self, dtype, seed):
permute = partial(permute_rows, seed)
permuted_array = compose(permute, partial(array, dtype=int64_dtype))
shape = (8, 8)
# Shuffle the input rows to verify that we correctly pick out the top
# values independently of order.
factor_data = permute(arange(0, 64, dtype=dtype).reshape(shape))
classifier_data = permuted_array([[0, 0, 1, 1, 2, 2, 0, 0],
[0, 0, 1, 1, 2, 2, 0, 0],
[0, 1, 2, 3, 0, 1, 2, 3],
[0, 1, 2, 3, 0, 1, 2, 3],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0]])
f = self.f
c = self.c
self.check_terms(
terms={
'top2': f.top(2, groupby=c),
'bottom2': f.bottom(2, groupby=c),
},
initial_workspace={
f: factor_data,
c: classifier_data,
},
expected={
# Should be the rightmost two entries in classifier_data,
# ignoring the off-diagonal.
'top2': permuted_array([[0, 1, 1, 1, 1, 1, 1, 0],
[0, 1, 1, 1, 1, 1, 0, 1],
[1, 1, 1, 1, 1, 0, 1, 1],
[1, 1, 1, 1, 0, 1, 1, 1],
[0, 1, 1, 0, 0, 0, 1, 1],
[0, 1, 0, 1, 0, 0, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1]], dtype=bool),
# Should be the rightmost two entries in classifier_data,
# ignoring the off-diagonal.
'bottom2': permuted_array([[1, 1, 1, 1, 1, 1, 0, 0],
[1, 1, 1, 1, 1, 1, 0, 0],
[1, 1, 1, 1, 1, 0, 1, 1],
[1, 1, 1, 1, 0, 1, 1, 1],
[1, 1, 0, 0, 1, 1, 0, 0],
[1, 1, 0, 0, 1, 1, 0, 0],
[1, 0, 1, 0, 0, 0, 0, 0],
[0, 1, 1, 0, 0, 0, 0, 0]],
dtype=bool),
},
mask=self.build_mask(permute(rot90(self.eye_mask(shape=shape)))),
)
+11
View File
@@ -400,6 +400,17 @@ class ObjectIdentityTestCase(TestCase):
method = getattr(f, funcname)
self.assertIs(method(), method())
def test_instance_caching_grouped_transforms(self):
f = SomeFactor()
c = GenericClassifier()
m = GenericFilter()
for meth in f.demean, f.zscore, f.rank:
self.assertIs(meth(), meth())
self.assertIs(meth(groupby=c), meth(groupby=c))
self.assertIs(meth(mask=m), meth(mask=m))
self.assertIs(meth(groupby=c, mask=m), meth(groupby=c, mask=m))
class SomeFactorParameterized(SomeFactor):
params = ('a', 'b')
+8 -2
View File
@@ -1,7 +1,11 @@
import numpy as np
def naive_grouped_rowwise_apply(data, group_labels, func, out=None):
def naive_grouped_rowwise_apply(data,
group_labels,
func,
func_args=(),
out=None):
"""
Simple implementation of grouped row-wise function application.
@@ -14,6 +18,8 @@ def naive_grouped_rowwise_apply(data, group_labels, func, out=None):
Should be the same shape as array.
func : function[ndarray[ndim=1]] -> function[ndarray[ndim=1]]
Function to apply to pieces of each row in array.
func_args : tuple
Additional positional arguments to provide to each row in array.
out : ndarray, optional
Array into which to write output. If not supplied, a new array of the
same shape as ``data`` is allocated and returned.
@@ -41,5 +47,5 @@ def naive_grouped_rowwise_apply(data, group_labels, func, out=None):
for (row, label_row, out_row) in zip(data, group_labels, out):
for label in np.unique(label_row):
locs = (label_row == label)
out_row[locs] = func(row[locs])
out_row[locs] = func(row[locs], *func_args)
return out
+7
View File
@@ -37,6 +37,13 @@ cpdef is_missing(ndarray data, object missing_value):
return (data == missing_value)
def rankdata_1d_descending(ndarray data, str method):
"""
1D descending version of scipy.stats.rankdata.
"""
return rankdata(-(data.view(float64)), method=method)
def masked_rankdata_2d(ndarray data,
ndarray mask,
object missing_value,
+50 -33
View File
@@ -5,12 +5,12 @@ from functools import wraps
from operator import attrgetter
from numbers import Number
from numpy import inf, where
from numpy import empty_like, inf, nan, where
from scipy.stats import rankdata
from zipline.errors import UnknownRankMethod
from zipline.lib.normalize import naive_grouped_rowwise_apply
from zipline.lib.rank import masked_rankdata_2d
from zipline.lib.rank import masked_rankdata_2d, rankdata_1d_descending
from zipline.pipeline.api_utils import restrict_to_dtype
from zipline.pipeline.classifiers import Classifier, Everything, Quantiles
from zipline.pipeline.expression import (
@@ -314,7 +314,6 @@ float64_only = restrict_to_dtype(
)
)
FACTOR_DTYPES = frozenset([datetime64ns_dtype, float64_dtype, int64_dtype])
@@ -501,16 +500,14 @@ class Factor(RestrictedDTypeMixin, ComputableTerm):
--------
:meth:`pandas.DataFrame.groupby`
"""
# This is a named function so that it has a __name__ for use in the
# graph repr of GroupedRowTransform.
def demean(row):
return row - nanmean(row)
return GroupedRowTransform(
transform=demean,
transform_args=(),
factor=self,
mask=mask,
groupby=groupby,
dtype=self.dtype,
missing_value=self.missing_value,
mask=mask,
)
@expect_types(
@@ -569,17 +566,14 @@ class Factor(RestrictedDTypeMixin, ComputableTerm):
--------
:meth:`pandas.DataFrame.groupby`
"""
# This is a named function so that it has a __name__ for use in the
# graph repr of GroupedRowTransform.
def zscore(row):
return (row - nanmean(row)) / nanstd(row)
return GroupedRowTransform(
transform=zscore,
transform_args=(),
factor=self,
mask=mask,
groupby=groupby,
window_safe=True,
dtype=self.dtype,
missing_value=self.missing_value,
mask=mask,
)
def rank(self,
@@ -631,17 +625,16 @@ class Factor(RestrictedDTypeMixin, ComputableTerm):
if groupby is NotSpecified:
return Rank(self, method=method, ascending=ascending, mask=mask)
else:
def rank(row):
return rankdata(row if ascending else -row, method=method)
return GroupedRowTransform(
transform=rank,
factor=self,
mask=mask,
groupby=groupby,
window_safe=True,
)
return GroupedRowTransform(
transform=rankdata if ascending else rankdata_1d_descending,
transform_args=(method,),
factor=self,
groupby=groupby,
dtype=float64_dtype,
missing_value=nan,
mask=mask,
window_safe=True,
)
@expect_types(
target=Term, correlation_length=int, mask=(Filter, NotSpecifiedType),
@@ -1113,6 +1106,8 @@ class GroupedRowTransform(Factor):
groupby : zipline.pipeline.Classifier
Classifier partitioning ``factor`` into groups to use when calculating
means.
transform_args : tuple[hashable]
Additional positional arguments to forward to ``transform``.
Notes
-----
@@ -1128,7 +1123,15 @@ class GroupedRowTransform(Factor):
"""
window_length = 0
def __new__(cls, transform, factor, mask, groupby, **kwargs):
def __new__(cls,
transform,
transform_args,
factor,
groupby,
dtype,
missing_value,
mask,
**kwargs):
if mask is NotSpecified:
mask = factor.mask
@@ -1141,22 +1144,25 @@ class GroupedRowTransform(Factor):
return super(GroupedRowTransform, cls).__new__(
GroupedRowTransform,
transform=transform,
transform_args=transform_args,
inputs=(factor, groupby),
missing_value=factor.missing_value,
missing_value=missing_value,
mask=mask,
dtype=factor.dtype,
dtype=dtype,
**kwargs
)
def _init(self, transform, *args, **kwargs):
def _init(self, transform, transform_args, *args, **kwargs):
self._transform = transform
self._transform_args = transform_args
return super(GroupedRowTransform, self)._init(*args, **kwargs)
@classmethod
def _static_identity(cls, transform, *args, **kwargs):
def _static_identity(cls, transform, transform_args, *args, **kwargs):
return (
super(GroupedRowTransform, cls)._static_identity(*args, **kwargs),
transform,
transform_args,
)
def _compute(self, arrays, dates, assets, mask):
@@ -1178,13 +1184,14 @@ class GroupedRowTransform(Factor):
# Make a copy with the null code written to masked locations.
group_labels = where(mask, group_labels, null_label)
return where(
group_labels != null_label,
naive_grouped_rowwise_apply(
data=data,
group_labels=group_labels,
func=self._transform,
func_args=self._transform_args,
out=empty_like(data, dtype=self.dtype),
),
self.missing_value,
)
@@ -1492,3 +1499,13 @@ class Latest(LatestMixin, CustomFactor):
def compute(self, today, assets, out, data):
out[:] = data[-1]
# Functions to be passed to GroupedRowTransform. These aren't defined inline
# because the transformation function is part of the instance hash key.
def demean(row):
return row - nanmean(row)
def zscore(row):
return (row - nanmean(row)) / nanstd(row)