datatable.py
from collections import OrderedDict
from enum import Enum
import backtrader as bt
from bokeh.models import ColumnDataSource, Paragraph, TableColumn, DataTable, \
DateFormatter, NumberFormatter, StringFormatter
from .params import get_params_str
# the height of a single row
ROW_HEIGHT = 25
class ColummDataType(Enum):
DATETIME = 1
FLOAT = 2
INT = 3
PERCENTAGE = 4
STRING = 5
class TableGenerator:
'''
Table generator for key -> value tuples
'''
def get_table(self, data):
table = [['Name'], ['Value']]
cds = ColumnDataSource()
columns = []
for n, v in data.items():
table[0].append(n)
table[1].append(v)
for i, c in enumerate(table):
col_name = f'col{i}'
cds.add(c[1:], col_name)
columns.append(TableColumn(
field=col_name,
title=c[0]))
column_height = len(table[0]) * ROW_HEIGHT
dtable = DataTable(
source=cds,
columns=columns,
index_position=None,
height=column_height,
width=0, # set width to 0 so there is no min_width
sizing_mode='stretch_width',
fit_columns=True)
return dtable
class AnalysisTableGenerator:
'''
Table generator for analyzers
'''
def __init__(self, scheme):
self._scheme = scheme
@staticmethod
def _get_table_generic(analyzer):
'''
Returns two columns labeled '' and 'Value'
'''
table = [
['', ColummDataType.STRING],
['Value', ColummDataType.STRING]]
def add_to_table(item, baselabel=''):
if isinstance(item, dict):
for ak, av in item.items():
label = f'{baselabel} - {ak}' if len(baselabel) > 0 else ak
if isinstance(av, (dict, bt.AutoOrderedDict, OrderedDict)):
add_to_table(av, label)
else:
table[0].append(label)
table[1].append(av)
add_to_table(analyzer.get_analysis())
return analyzer.__class__.__name__, [table]
def _get_formatter(self, ctype):
if ctype == ColummDataType.FLOAT:
return NumberFormatter(format=self._scheme.number_format)
elif ctype == ColummDataType.INT:
return NumberFormatter()
elif ctype == ColummDataType.DATETIME:
return DateFormatter(format='%c')
elif ctype == ColummDataType.STRING:
return StringFormatter()
elif ctype == ColummDataType.PERCENTAGE:
return NumberFormatter(format='0.000 %')
else:
raise Exception(f'Unsupported ColumnDataType: "{ctype}"')
def get_tables(self, analyzer):
'''
Return a header for this analyzer and one *or more* data tables.
'''
if hasattr(analyzer, 'get_analysis_table'):
title, table_columns_list = analyzer.get_analysis_table()
else:
# Analyzer does not provide a table function. Use our generic one
title, table_columns_list = __class__._get_table_generic(
analyzer)
# don't add empty analyzer
if len(table_columns_list[0][0]) == 2:
return None, None
param_str = get_params_str(analyzer.params)
if len(param_str) > 0:
title += f' ({param_str})'
elems = []
for table_columns in table_columns_list:
cds = ColumnDataSource()
columns = []
for i, c in enumerate(table_columns):
col_name = f'col{i}'
cds.add(c[2:], col_name)
columns.append(TableColumn(
field=col_name,
title=c[0],
formatter=self._get_formatter(c[1])))
# define height of column by multiplying count of rows
# with ROW_HEIGHT
column_height = len(table_columns[0]) * ROW_HEIGHT
elems.append(DataTable(
source=cds,
columns=columns,
index_position=None,
height=column_height,
width=0, # set width to 0 so there is no min_width
sizing_mode='stretch_width',
fit_columns=True))
return Paragraph(
text=title,
css_classes=['table-title']), elems
