1 | from asap.scantable import scantable |
---|
2 | from asap import rcParams |
---|
3 | from asap import print_log |
---|
4 | |
---|
5 | def average_time(*args, **kwargs): |
---|
6 | """ |
---|
7 | Return the (time) average of a scan or list of scans. [in channels only] |
---|
8 | The cursor of the output scan is set to 0 |
---|
9 | Parameters: |
---|
10 | one scan or comma separated scans |
---|
11 | mask: an optional mask (only used for 'var' and 'tsys' weighting) |
---|
12 | scanav: True averages each scan separately. |
---|
13 | False (default) averages all scans together, |
---|
14 | weight: Weighting scheme. |
---|
15 | 'none' (mean no weight) |
---|
16 | 'var' (1/var(spec) weighted) |
---|
17 | 'tsys' (1/Tsys**2 weighted) |
---|
18 | 'tint' (integration time weighted) |
---|
19 | 'tintsys' (Tint/Tsys**2) |
---|
20 | 'median' ( median averaging) |
---|
21 | align: align the spectra in velocity before averaging. It takes |
---|
22 | the time of the first spectrum in the first scantable |
---|
23 | as reference time. |
---|
24 | Example: |
---|
25 | # return a time averaged scan from scana and scanb |
---|
26 | # without using a mask |
---|
27 | scanav = average_time(scana,scanb) |
---|
28 | # return the (time) averaged scan, i.e. the average of |
---|
29 | # all correlator cycles |
---|
30 | scanav = average_time(scan, scanav=True) |
---|
31 | """ |
---|
32 | scanav = False |
---|
33 | if kwargs.has_key('scanav'): |
---|
34 | scanav = kwargs.get('scanav') |
---|
35 | weight = 'tint' |
---|
36 | if kwargs.has_key('weight'): |
---|
37 | weight = kwargs.get('weight') |
---|
38 | mask = () |
---|
39 | if kwargs.has_key('mask'): |
---|
40 | mask = kwargs.get('mask') |
---|
41 | align = False |
---|
42 | if kwargs.has_key('align'): |
---|
43 | align = kwargs.get('align') |
---|
44 | varlist = vars() |
---|
45 | if isinstance(args[0],list): |
---|
46 | lst = args[0] |
---|
47 | elif isinstance(args[0],tuple): |
---|
48 | lst = list(args[0]) |
---|
49 | else: |
---|
50 | lst = list(args) |
---|
51 | |
---|
52 | del varlist["kwargs"] |
---|
53 | varlist["args"] = "%d scantables" % len(lst) |
---|
54 | # need special formatting here for history... |
---|
55 | |
---|
56 | from asap._asap import stmath |
---|
57 | stm = stmath() |
---|
58 | for s in lst: |
---|
59 | if not isinstance(s,scantable): |
---|
60 | msg = "Please give a list of scantables" |
---|
61 | if rcParams['verbose']: |
---|
62 | print msg |
---|
63 | return |
---|
64 | else: |
---|
65 | raise TypeError(msg) |
---|
66 | if scanav: scanav = "SCAN" |
---|
67 | else: scanav = "NONE" |
---|
68 | alignedlst = [] |
---|
69 | if align: |
---|
70 | refepoch = lst[0].get_time(0) |
---|
71 | for scan in lst: |
---|
72 | alignedlst.append(scan.freq_align(refepoch,insitu=False)) |
---|
73 | else: |
---|
74 | alignedlst = lst |
---|
75 | if weight.upper() == 'MEDIAN': |
---|
76 | # median doesn't support list of scantables - merge first |
---|
77 | merged = None |
---|
78 | if len(alignedlst) > 1: |
---|
79 | merged = merge(alignedlst) |
---|
80 | else: |
---|
81 | merged = alignedlst[0] |
---|
82 | s = scantable(stm._averagechannel(merged, 'MEDIAN', scanav)) |
---|
83 | del merged |
---|
84 | else: |
---|
85 | s = scantable(stm._average(alignedlst, mask, weight.upper(), scanav)) |
---|
86 | s._add_history("average_time",varlist) |
---|
87 | print_log() |
---|
88 | return s |
---|
89 | |
---|
90 | def quotient(source, reference, preserve=True): |
---|
91 | """ |
---|
92 | Return the quotient of a 'source' (signal) scan and a 'reference' scan. |
---|
93 | The reference can have just one scan, even if the signal has many. Otherwise |
---|
94 | they must have the same number of scans. |
---|
95 | The cursor of the output scan is set to 0 |
---|
96 | Parameters: |
---|
97 | source: the 'on' scan |
---|
98 | reference: the 'off' scan |
---|
99 | preserve: you can preserve (default) the continuum or |
---|
100 | remove it. The equations used are |
---|
101 | preserve: Output = Toff * (on/off) - Toff |
---|
102 | remove: Output = Toff * (on/off) - Ton |
---|
103 | """ |
---|
104 | varlist = vars() |
---|
105 | from asap._asap import stmath |
---|
106 | stm = stmath() |
---|
107 | stm._setinsitu(False) |
---|
108 | s = scantable(stm._quotient(source, reference, preserve)) |
---|
109 | s._add_history("quotient",varlist) |
---|
110 | print_log() |
---|
111 | return s |
---|
112 | |
---|
113 | def simple_math(left, right, op='add', tsys=True): |
---|
114 | """ |
---|
115 | Apply simple mathematical binary operations to two |
---|
116 | scan tables, returning the result in a new scan table. |
---|
117 | The operation is applied to both the correlations and the TSys data |
---|
118 | The cursor of the output scan is set to 0 |
---|
119 | Parameters: |
---|
120 | left: the 'left' scan |
---|
121 | right: the 'right' scan |
---|
122 | op: the operation: 'add' (default), 'sub', 'mul', 'div' |
---|
123 | tsys: if True (default) then apply the operation to Tsys |
---|
124 | as well as the data |
---|
125 | """ |
---|
126 | varlist = vars() |
---|
127 | print "Not yet available in asap" |
---|
128 | return |
---|
129 | if not isinstance(left,scantable) and not isinstance(right,scantable): |
---|
130 | msg = "Please provide two scantables as input" |
---|
131 | if rcParams['verbose']: |
---|
132 | print msg |
---|
133 | return |
---|
134 | else: |
---|
135 | raise TypeError(msg) |
---|
136 | s = scantable(stm._bop(left, right, op, tsys)) |
---|
137 | s._add_history("simple_math", varlist) |
---|
138 | print_log() |
---|
139 | return s |
---|
140 | |
---|
141 | def merge(*args): |
---|
142 | """ |
---|
143 | """ |
---|
144 | varlist = vars() |
---|
145 | if isinstance(args[0],list): |
---|
146 | lst = tuple(args[0]) |
---|
147 | elif isinstance(args[0],tuple): |
---|
148 | lst = args[0] |
---|
149 | else: |
---|
150 | lst = tuple(args) |
---|
151 | varlist["args"] = "%d scantables" % len(lst) |
---|
152 | # need special formatting her for history... |
---|
153 | from asap._asap import stmath |
---|
154 | stm = stmath() |
---|
155 | for s in lst: |
---|
156 | if not isinstance(s,scantable): |
---|
157 | msg = "Please give a list of scantables" |
---|
158 | if rcParams['verbose']: |
---|
159 | print msg |
---|
160 | return |
---|
161 | else: |
---|
162 | raise TypeError(msg) |
---|
163 | s = scantable(stm._merge(lst)) |
---|
164 | s._add_history("merge", varlist) |
---|
165 | print_log() |
---|
166 | return s |
---|
167 | |
---|