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
|
'''
Created on Nov 20, 2012
@author: steger
'''
from DataProcessing.DataReader import DataReader
from DataProcessing.DataHeader import DataHeader
from DataProcessing.DataSource import DataSource
from DataProcessing.Data import Data
from DataProcessing.DataError import SamplerError
class Sampler(DataSource):
'''
classdocs
'''
def __init__(self, datasource):
'''
Constructor
@param datasource: table of records to manipulate with
@type datasource: DataSource
'''
if not isinstance(datasource, DataSource):
raise SamplerError("Wrong type of datasource %s" % datasource)
DataSource.__init__(self, datasource)
self._reader = DataReader(datasource = datasource._data)
header = DataHeader("%sSample(%s)" % (self.name, self.source.name))
for c in self._reader.headercells():
header.addColumn(c)
self._data = Data(self.um, header)
@property
def header(self):
return self._data.header
def __len__(self):
self.process()
return len(self._data)
def __getitem__(self, k):
return self._data._rawrecords.__getitem__(k)
class Head(Sampler):
def __init__(self, datasource, head = 10):
'''
Constructor
@param datasource: table of records to manipulate with
@type datasource: DataSource
@param head: the top n records of the table
@type head: int
'''
Sampler.__init__(self, datasource)
self._head = head
@property
def name(self):
return "Head"
@property
def head(self):
return self._head
@head.setter
def head(self, head):
self._head = int(head)
self._data.clear()
self._reader.rewind()
def _process(self):
if self._reader.sourceCleared.isSet():
self._reader.sourceCleared.clear()
self._reader.rewind()
self._data.clear()
if len(self._data) == self.head:
return
for x in self._reader:
self._data._rawrecords.append(x)
if len(self._data) == self.head:
self._data._onexpand()
return
raise SamplerError("Not enough sample %d/%d" % (len(self._data), self.head))
class Tail(Sampler):
def __init__(self, datasource, tail = 10):
'''
Constructor
@param datasource: table of records to manipulate with
@type datasource: DataSource
@param tail: the last n records of the table
@type tail: int
'''
Sampler.__init__(self, datasource)
self._tail = tail
@property
def name(self):
return "Tail"
@property
def tail(self):
return self._tail
@tail.setter
def tail(self, tail):
self._tail = int(tail)
self._data.clear()
self._reader.rewind()
def _process(self):
clear = False
if self._reader.sourceCleared.isSet():
self._reader.sourceCleared.clear()
self._reader.rewind()
self._data.clear()
for x in self._reader:
if len(self._data) == self.tail:
self._data._rawrecords.pop(0)
clear = True
self._data._rawrecords.append(x)
if clear:
self._data._onclear()
if len(self._data) == self.tail:
self._data._onexpand()
else:
raise SamplerError("Not enough sample %d/%d" % (len(self._data), self.tail))
class Sorter(Sampler):
def __init__(self, datasource, keycell = None, ascending = True):
'''
Constructor
@param datasource: table of records to manipulate with
@type datasource: DataSource
@param keycell: the key column to use for sorting
@type keycell: CellRequest or None
@param ascending: indicate the sortin order
@type ascending: bool
'''
Sampler.__init__(self, datasource)
self._asc = ascending
self._key = 0
if keycell:
self.keycell = keycell
@property
def name(self):
return "Sort"
@property
def ascending(self):
return self._asc
@ascending.setter
def ascending(self, ascending):
if bool(ascending) != self._asc:
self._asc = bool(ascending)
self._data.clear()
self._reader.rewind()
@property
def key(self):
return self._key
@key.setter
def key(self, key):
self._key = int(key)
@property
def keycell(self):
raise SamplerError("don't read this property")
@keycell.setter
def keycell(self, cellrequest):
for idx, _ in self.source.header.getCell(cellrequest):
self._key = idx
break
def _process(self):
clear = False
if self._reader.sourceCleared.isSet():
self._reader.sourceCleared.clear()
clear = True
if self._reader.sourceExpanded.isSet():
self._reader.sourceExpanded.clear()
clear = True
if not clear:
return
self._reader.rewind()
self._data.clear()
self._data._rawrecords = sorted(self._reader.source._rawrecords, key=lambda r: r[self.key], reverse = not self.ascending)
if len(self._data):
self._data._onclear()
self._data._onexpand()
else:
raise SamplerError("Not enough sample...")
|