source: trunk/python/selector.py@ 1549

Last change on this file since 1549 was 1542, checked in by Malte Marquarding, 16 years ago

applied python taql style at the wrong level

File size: 6.5 KB
Line 
1from asap._asap import selector as _selector
2from asap import unique, _to_list
3
4class selector(_selector):
5 """
6 A selection object to be applied to scantables to restrict the
7 scantables to specific rows.
8 """
9 def __init(self):
10 _selector.__init__(self)
11
12 def reset(self):
13 """
14 Unset all selections.
15 """
16 self._reset()
17
18 def is_empty(self):
19 """
20 Has anything been set?
21 """
22 return self._empty()
23
24 def set_polarisations(self, pols=[]):
25 """
26 Set the polarisations to be selected in the scantable.
27 Parameters:
28 pols: a list of integers of 0-3, or strings, e.g ["I","Q"].
29 Default [] is no selection
30 Example:
31 sel = selector()
32 # These are equivalent if data is 'linear'
33 sel.set_polarisations(["XX","Re(XY)"])
34 sel.set_polarisations([0,2])
35 # reset the polarisation selection
36 sel.set_polarisations()
37
38 """
39 vec = _to_list(pols, str) or _to_list(pols, int)
40 if isinstance(vec, list): # is an empty and/or valid vector
41 if len(vec) and isinstance(vec[-1],str):
42 self._setpolstrings(vec)
43 return
44 self._setpols(vec)
45 else:
46 raise TypeError('Unknown pol type. Please use [0,1...] or ["XX","YY"...]')
47
48 # for the americans
49 set_polarizations = set_polarisations
50 # for the lazy
51 set_pols = set_polarisations
52
53 def set_ifs(self, ifs=[]):
54 """
55 Set a sequence of IF numbers (0-based).
56 Parameters:
57 ifs: a list of integers. Default [] is to unset the selection.
58 """
59 vec = _to_list(ifs, int)
60 if isinstance(vec,list):
61 self._setifs(vec)
62 else:
63 raise TypeError('Unknown IFno type. Use lists of integers.')
64
65 def set_scans(self, scans=[]):
66 """
67 Set a sequence of Scan numbers (0-based).
68 Parameters:
69 scans: a list of integers. Default [] is to unset the selection.
70 """
71 vec = _to_list(scans, int)
72 if isinstance(vec,list):
73 self._setscans(vec)
74 else:
75 raise TypeError('Unknown Scan number type. Use lists of integers.')
76
77 def set_beams(self, beams=[]):
78 """
79 Set a sequence of Beam numbers (0-based).
80 Parameters:
81 beams: a list of integers. Default [] is to unset the selection.
82 """
83 vec = _to_list(beams, int)
84 if isinstance(vec,list):
85 self._setbeams(vec)
86 else:
87 raise TypeError('Unknown Beam number type. Use lists of integers.')
88
89 def set_cycles(self, cycles=[]):
90 """
91 Set a sequence of IF numbers (0-based).
92 Parameters:
93 cycless: a list of integers. Default [] is to unset the selection.
94 """
95 vec = _to_list(cycles, int)
96 if isinstance(vec,list):
97 self._setcycles(vec)
98 else:
99 raise TypeError('Unknown Cycle number type. Use lists of integers.')
100
101
102 def set_name(self, name):
103 """
104 Set a selection based on a name. This can be a unix pattern , e.g. "*_R"
105 Parameters:
106 name: a string containing a source name or pattern
107 Examples:
108 # select all reference scans which start with "Orion"
109 selection.set_name("Orion*_R")
110 """
111 if isinstance(name, str):
112 self._setname(name)
113 else:
114 raise TypeError('name must be a string')
115
116 def set_tsys(self, tsysmin=0.0, tsysmax=None):
117 """
118 Select by Tsys range.
119 Parameters:
120 tsysmin: the lower threshold. Default 0.0
121 tsysmax: the upper threshold. Default None.
122 Examples:
123 # select all spectra with Tsys <= 500.0
124 selection.set_tsys(tsysmax=500.0)
125
126 """
127 taql = "SELECT FROM $1 WHERE TSYS[0] >= %f" % (tsysmin)
128 if isinstance(tsysmax, float):
129 taql = taql + " AND TSYS[0] <= %f" % ( tsysmax)
130 self._settaql(taql)
131
132 def set_query(self, query):
133 """
134 Select by Column query. Power users only!
135 Example:
136 # select all off scans with integration times over 60 seconds.
137 selection.set_query("SRCTYPE == 1 AND INTERVAL > 60.0")
138 """
139 taql = "SELECT FROM $1 WHERE " + query
140 self._settaql(taql)
141
142 def set_order(self, order):
143 """
144 Set the order the scantable should be sorted by.
145 Parameters:
146 order: The list of column names to sort by in order
147 """
148 self._setorder(order)
149
150 def get_scans(self):
151 return list(self._getscans())
152 def get_cycles(self):
153 return list(self._getcycles())
154 def get_beams(self):
155 return list(self._getbeams())
156 def get_ifs(self):
157 return list(self._getifs())
158 def get_pols(self):
159 return list(self._getpols())
160 def get_poltypes(self):
161 return list(self._getpoltypes())
162 def get_order(self):
163 return list(self._getorder())
164 def get_query(self):
165 prefix = "SELECT FROM $1 WHERE "
166 return self._gettaql().replace(prefix, "")
167
168 def get_name(self):
169 print "NYI"
170 s = self._gettaql()
171 return
172 def __str__(self):
173 out = ""
174 d = {"SCANNO": self.get_scans(),
175 "CYCLENO": self.get_cycles(),
176 "BEAMNO": self.get_beams(),
177 "IFNO": self.get_ifs(),
178 "Pol Type": self.get_poltypes(),
179 "POLNO": self.get_pols(),
180 "QUERY": self.get_query(),
181 "Sort Order": self.get_order()
182 }
183 for k,v in d.iteritems():
184 if v:
185 out += "%s: %s\n" % (k, v)
186 if len(out):
187 return out[:-1]
188 else:
189 return out
190 def __add__(self, other):
191 """
192 Merge two selections.
193 """
194 union = selector()
195 gets = [[self._getscans(), other._getscans(), union._setscans],
196 [self._getcycles(), other._getcycles(),union._setcycles],
197 [self._getbeams(), other._getbeams(), union._setbeams],
198 [self._getifs(), other._getifs(), union._setifs],
199 [self._getpols(), other._getpols(), union._setpols]]
200 for v in gets:
201 vec = list(v[0]+v[1])
202 vec.sort()
203 v[2](unique(vec))
204 q = other.get_query()
205 qs = self.get_query()
206 if len(q) and len(qs):
207 union.set_query(qs +" AND " + q)
208 else:
209 if len(q):
210 union.set_query(q)
211 elif len(qs):
212 union.set_query(qs)
213 return union
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