MAINT: generalize the (next|previous)_earnings_date_frame functions

This commit is contained in:
Joe Jevnik
2016-01-05 14:05:05 -05:00
parent b037a06576
commit 826115acdf
2 changed files with 93 additions and 85 deletions
+3 -85
View File
@@ -3,16 +3,14 @@ Reference implementation for EarningsCalendar loaders.
"""
from itertools import repeat
from numpy import full_like, full
import pandas as pd
from six import iteritems
from six.moves import zip
from toolz import merge
from .base import PipelineLoader
from .frame import DataFrameLoader
from .utils import next_date_frame, previous_date_frame
from ..data.earnings import EarningsCalendar
from zipline.utils.numpy_utils import np_NaT
from zipline.utils.memoize import lazyval
@@ -83,7 +81,7 @@ class EarningsCalendarLoader(PipelineLoader):
def next_announcement_loader(self):
return DataFrameLoader(
self.dataset.next_announcement,
next_earnings_date_frame(
next_date_frame(
self.all_dates,
self.announcement_dates,
),
@@ -94,7 +92,7 @@ class EarningsCalendarLoader(PipelineLoader):
def previous_announcement_loader(self):
return DataFrameLoader(
self.dataset.previous_announcement,
previous_earnings_date_frame(
previous_date_frame(
self.all_dates,
self.announcement_dates,
),
@@ -110,83 +108,3 @@ class EarningsCalendarLoader(PipelineLoader):
)
def next_earnings_date_frame(dates, announcement_dates):
"""
Make a DataFrame representing simulated next earnings dates.
Parameters
----------
dates : pd.DatetimeIndex.
The index of the returned DataFrame.
announcement_dates : dict[int -> pd.Series]
Dict mapping sids to an index of dates on which earnings were announced
for that sid.
Returns
-------
next_earnings: pd.DataFrame
A DataFrame representing, for each (label, date) pair, the first entry
in `earnings_calendars[label]` on or after `date`. Entries falling
after the last date in a calendar will have `np_NaT` as the result in
the output.
See Also
--------
previous_earnings_date_frame
"""
cols = {equity: full_like(dates, np_NaT) for equity in announcement_dates}
raw_dates = dates.values
for equity, earnings_dates in iteritems(announcement_dates):
data = cols[equity]
if not earnings_dates.index.is_monotonic_increasing:
earnings_dates = earnings_dates.sort_index()
# Iterate over the raw Series values, since we're comparing against
# numpy arrays anyway.
iterkv = zip(earnings_dates.index.values, earnings_dates.values)
for timestamp, announce_date in iterkv:
date_mask = (timestamp <= raw_dates) & (raw_dates <= announce_date)
value_mask = (announce_date <= data) | (data == np_NaT)
data[date_mask & value_mask] = announce_date
return pd.DataFrame(index=dates, data=cols)
def previous_earnings_date_frame(dates, announcement_dates):
"""
Make a DataFrame representing simulated next earnings dates.
Parameters
----------
dates : DatetimeIndex.
The index of the returned DataFrame.
announcement_dates : dict[int -> DatetimeIndex]
Dict mapping sids to an index of dates on which earnings were announced
for that sid.
Returns
-------
prev_earnings: pd.DataFrame
A DataFrame representing, for (label, date) pair, the first entry in
`announcement_dates[label]` strictly before `date`. Entries falling
before the first date in a calendar will have `NaT` as the result in
the output.
See Also
--------
next_earnings_date_frame
"""
sids = list(announcement_dates)
out = full((len(dates), len(sids)), np_NaT, dtype='datetime64[ns]')
dn = dates[-1].asm8
for col_idx, sid in enumerate(sids):
# announcement_dates[sid] is Series mapping knowledge_date to actual
# announcement date. We don't care about the knowledge date for
# computing previous earnings.
values = announcement_dates[sid].values
values = values[values <= dn]
out[dates.searchsorted(values), col_idx] = values
frame = pd.DataFrame(out, index=dates, columns=sids)
frame.ffill(inplace=True)
return frame
+90
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@@ -0,0 +1,90 @@
import numpy as np
import pandas as pd
from six import iteritems
from six.moves import zip
from zipline.utils.numpy_utils import np_NaT
def next_date_frame(dates, announcement_dates):
"""
Make a DataFrame representing simulated next earnings dates.
Parameters
----------
dates : pd.DatetimeIndex.
The index of the returned DataFrame.
announcement_dates : dict[int -> pd.Series]
Dict mapping sids to an index of dates on which earnings were announced
for that sid.
Returns
-------
next_earnings: pd.DataFrame
A DataFrame representing, for each (label, date) pair, the first entry
in `earnings_calendars[label]` on or after `date`. Entries falling
after the last date in a calendar will have `np_NaT` as the result in
the output.
See Also
--------
previous_earnings_date_frame
"""
cols = {
equity: np.full_like(dates, np_NaT) for equity in announcement_dates
}
raw_dates = dates.values
for equity, earnings_dates in iteritems(announcement_dates):
data = cols[equity]
if not earnings_dates.index.is_monotonic_increasing:
earnings_dates = earnings_dates.sort_index()
# Iterate over the raw Series values, since we're comparing against
# numpy arrays anyway.
iterkv = zip(earnings_dates.index.values, earnings_dates.values)
for timestamp, announce_date in iterkv:
date_mask = (timestamp <= raw_dates) & (raw_dates <= announce_date)
value_mask = (announce_date <= data) | (data == np_NaT)
data[date_mask & value_mask] = announce_date
return pd.DataFrame(index=dates, data=cols)
def previous_date_frame(dates, announcement_dates):
"""
Make a DataFrame representing simulated next earnings dates.
Parameters
----------
dates : DatetimeIndex.
The index of the returned DataFrame.
announcement_dates : dict[int -> DatetimeIndex]
Dict mapping sids to an index of dates on which earnings were announced
for that sid.
Returns
-------
prev_earnings: pd.DataFrame
A DataFrame representing, for (label, date) pair, the first entry in
`announcement_dates[label]` strictly before `date`. Entries falling
before the first date in a calendar will have `NaT` as the result in
the output.
See Also
--------
next_earnings_date_frame
"""
sids = list(announcement_dates)
out = np.full((len(dates), len(sids)), np_NaT, dtype='datetime64[ns]')
dn = dates[-1].asm8
for col_idx, sid in enumerate(sids):
# announcement_dates[sid] is Series mapping knowledge_date to actual
# announcement date. We don't care about the knowledge date for
# computing previous earnings.
values = announcement_dates[sid].values
values = values[values <= dn]
out[dates.searchsorted(values), col_idx] = values
frame = pd.DataFrame(out, index=dates, columns=sids)
frame.ffill(inplace=True)
return frame