1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
import itertools
from typing import Dict, List
class DataFrame:
"""Table-like class for storing a 2D cells table with named columns."""
def __init__(self, data: Dict[str, List[object]] = {}):
"""
Create a new DataFrame from a dictionary (keys = headers,
values = columns).
"""
self._headers = [i for i in data.keys()]
self._rows = []
row_num = 0
def get_data_row(idx):
r = {}
for header, header_data in data.items():
if not len(header_data) > idx:
continue
r[header] = header_data[idx]
return r
while True:
row_dict = get_data_row(row_num)
if len(row_dict) == 0:
break
self._append_row(row_dict.keys(), row_dict.values())
row_num = row_num + 1
def concat_rows(self, other: 'DataFrame') -> None:
"""
In-place concatenate rows of other into the rows of the
current DataFrame.
None is added in pre-existing cells if new headers
are introduced.
"""
other_datas = other._data_only()
other_headers = other.headers
for d in other_datas:
self._append_row(other_headers, d)
def _append_row(self, headers: List[str], data: List[object]):
new_row = {k:v for k,v in zip(headers, data)}
self._rows.append(new_row)
for header in headers:
if not header in self._headers:
self._headers.append(header)
def __repr__(self):
# return repr(self._rows)
repr = ""
header_list = self._headers_only()
row_format = u""
for header in header_list:
row_format = row_format + u"{:>%d}" %(len(header) + 1)
repr = row_format.format(*header_list) + "\n"
for v in self._data_only():
repr = repr + row_format.format(*v) + "\n"
return repr
def __eq__(self, other):
if isinstance(other, self.__class__):
return self.headers == other.headers and self.data_table == other.data_table
else:
print("wrong instance", other.__class__)
return False
@property
def headers(self) -> List[str]:
return [i for i in self._headers_only()]
@property
def data_table(self) -> List[List[object]]:
return list(self._data_only())
@property
def data_table_transposed(self) -> List[List[object]]:
return list(self._transposed_data())
@property
def data_row_len(self) -> int:
return len(self._rows)
def data_row_at(self, idx) -> List[object]:
"""
Return a single data row at the specified index (0th based).
Accepts negative indices, e.g. -1 is last row.
"""
row_dict = self._rows[idx]
l = []
for h in self._headers_only():
l.append(row_dict.get(h)) # Adds None in blank spots.
return l
def copy(self) -> 'DataFrame':
"""
Shallow copy of this DataFrame.
"""
return self.repeat(count=0)
def repeat(self, count: int) -> 'DataFrame':
"""
Returns a new DataFrame where each row of this dataframe is repeated count times.
A repeat of a row is adjacent to other repeats of that same row.
"""
df = DataFrame()
df._headers = self._headers.copy()
rows = []
for row in self._rows:
for i in range(count):
rows.append(row.copy())
df._rows = rows
return df
def merge_data_columns(self, other: 'DataFrame'):
"""
Merge self and another DataFrame by adding the data from other column-wise.
For any headers that are the same, data from 'other' is preferred.
"""
for h in other._headers:
if not h in self._headers:
self._headers.append(h)
append_rows = []
for self_dict, other_dict in itertools.zip_longest(self._rows, other._rows):
if not self_dict:
d = {}
append_rows.append(d)
else:
d = self_dict
d_other = other_dict
if d_other:
for k,v in d_other.items():
d[k] = v
for r in append_rows:
self._rows.append(r)
def data_row_reduce(self, fnc) -> 'DataFrame':
"""
Reduces the data row-wise by applying the fnc to each row (column-wise).
Empty cells are skipped.
fnc(Iterable[object]) -> object
fnc is applied over every non-empty cell in that column (descending row-wise).
Example:
DataFrame({'a':[1,2,3]}).data_row_reduce(sum) == DataFrame({'a':[6]})
Returns a new single-row DataFrame.
"""
df = DataFrame()
df._headers = self._headers.copy()
def yield_by_column(header_key):
for row_dict in self._rows:
val = row_dict.get(header_key)
if val:
yield val
new_row_dict = {}
for h in df._headers:
cell_value = fnc(yield_by_column(h))
new_row_dict[h] = cell_value
df._rows = [new_row_dict]
return df
def _headers_only(self):
return self._headers
def _data_only(self):
row_len = len(self._rows)
for i in range(row_len):
yield self.data_row_at(i)
def _transposed_data(self):
return zip(*self._data_only())
|