| [680] | 1 | <html> | 
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|  | 2 | <head> | 
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|  | 3 | <title>Batch processing tutorial</title> | 
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|  | 4 | <style type="text/css" media="all"> | 
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|  | 6 | background-color: #dbfff9; | 
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|  | 8 | } | 
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|  | 9 | div.code { | 
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|  | 13 | div.main { | 
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|  | 14 | margin: 0.2em 0.2em 0.2em 0.2em; | 
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|  | 15 | text-align: left; | 
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|  | 16 | font-family: sans-serif; | 
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|  | 17 | width: auto; | 
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|  | 18 | } | 
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|  | 19 | h1.custom { | 
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|  | 20 | background-color: #aaaaaa; | 
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|  | 21 | color: #000000; | 
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|  | 23 | font-family: sans-serif; | 
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|  | 24 | font-size: x-large; | 
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|  | 25 | } | 
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|  | 26 | </style> | 
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|  | 27 | </head> | 
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|  | 28 | <body> | 
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|  | 29 | <div> | 
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|  | 30 | <h1 class=custom> | 
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|  | 31 | Introduction | 
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|  | 32 | </h1> | 
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|  | 33 | <div class=main align=center> | 
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|  | 34 | This tutorial is aimed at observers who want to "batch reduce" their | 
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|  | 35 | data, i.e. process multiple files the same way. | 
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|  | 36 | </div> | 
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|  | 37 | <h1 class=custom> | 
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|  | 38 | Part I - Need to knows | 
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|  | 39 | </h1> | 
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|  | 40 | <div class=main align=center> | 
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|  | 41 | As ASAP is python based, we need to know a few commands and expression. | 
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|  | 42 | Python has "lists", which are basically vectors. We will use | 
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|  | 43 | these extensively.<br> | 
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|  | 44 | <div class=code><pre> | 
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|  | 45 | x = range(5) # creates a vector of length 5, x = [0,1,2,3,4] | 
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|  | 46 | len(x)       # gives the length of the vector | 
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|  | 47 | x[0]         # gets the first element of the vector | 
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|  | 48 | x[-1]        # gets the last element of the vector | 
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|  | 49 | </pre></div> | 
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|  | 50 | "for" loops are very useful. The code which should be run in the loop | 
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|  | 51 | has to be indented. The end of the loop is indicated by the fact that | 
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|  | 52 | the next command is aligned with the for.<br> | 
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|  | 53 | The following code prints out the numbers [0..4] | 
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|  | 54 | <div class=code><pre> | 
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|  | 55 | for i in range(5): | 
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|  | 56 | print i | 
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|  | 57 | </pre></div> | 
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|  | 58 | Vectors can also be filled: | 
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|  | 59 | <div class=code><pre> | 
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|  | 60 | x = [] # empty | 
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|  | 61 | for i in range(5): | 
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|  | 62 | x.append(i*5) | 
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|  | 63 | </pre></div> | 
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|  | 64 | The output is x = [0,5,10,15,20]<br> | 
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|  | 65 | Now we can access those elements like we did above (by index), or directly: | 
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|  | 66 | <div class=code><pre> | 
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|  | 67 | for i in x: | 
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|  | 68 | print i | 
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|  | 69 | </pre></div> | 
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|  | 70 | That's all we need to know! | 
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|  | 71 |  | 
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|  | 72 | </div> | 
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|  | 73 | <h1 class=custom> | 
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|  | 74 | Part II - the code | 
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|  | 75 | </h1> | 
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|  | 76 | <div class=main align=center> | 
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|  | 77 | This shows example code to process multiple files.<p> | 
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|  | 78 | Let's say we have three files (a.rpf, b.rpf, c.rpf)  which contain | 
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|  | 79 | on/off pairs and we want to get the quotients<br> | 
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|  | 80 | <div class=code><pre> | 
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|  | 81 | fnames = ["a.rpf","b.rpf","c.rpf"] # First we set up a vector of filenames | 
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|  | 82 | vec = []                           # a vector to hold the scantables | 
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|  | 83 | for f in fnames: | 
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|  | 84 | vec.append(scantable(f))        # fill the vector with scantables | 
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|  | 85 | </pre></div> | 
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|  | 86 | Then we can loop over all scantables: | 
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|  | 87 | <div class=code><pre> | 
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|  | 88 | quotients = []                        # to hold the quotient scantables | 
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|  | 89 | for scan in vec:                      # loop over input scantables | 
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| [1040] | 90 | quotients.append(scan.auto_quotient()) # add this quotient to the vector | 
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| [680] | 91 | </pre></div> | 
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|  | 92 | Let's have a look at the vector, and subtract a baseline | 
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|  | 93 | <div class=code><pre> | 
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|  | 94 | for q in quotients: | 
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|  | 95 | print q | 
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| [1040] | 96 | q.auto_poly_baseline(order=1,insitu=True) | 
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| [680] | 97 | </pre></div> | 
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|  | 98 | Now we average the lot together: | 
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|  | 99 | <div class=code><pre> | 
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|  | 100 | av = average_time(quotients) | 
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|  | 101 | </pre></div> | 
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|  | 102 |  | 
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|  | 103 | </div> | 
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|  | 104 | <h1 class=custom> | 
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|  | 105 | Appendix | 
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|  | 106 | </h1> | 
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|  | 107 | <div class=main align=center> | 
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|  | 108 | More info can be found on the ASAP homepage | 
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|  | 109 | <a href="http://www.atnf.csiro.au/computing/software/asap"> | 
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|  | 110 | http://www.atnf.csiro.au/computing/software/asap</a> | 
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|  | 111 | </div> | 
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|  | 112 | </body> | 
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|  | 113 | </html> | 
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