Changes between Version 5 and Version 6 of Dvo_tutorial
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- May 6, 2009, 3:34:23 AM (17 years ago)
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Dvo_tutorial
v5 v6 1 Started by [wiki:User:Sebastian.Jester Sebastian Jester]1 Started by Sebastian Jester 2 2 3 3 = More info = … … 13 13 dvo stores data in subdirectories of a CATDIR that correspond to different parts of the sky. This naturally allows comparatively fast spatial indexing. 14 14 15 Correspondingly, dvo operations are typically done on a given <code>region</code>of the sky.15 Correspondingly, dvo operations are typically done on a given `region` of the sky. 16 16 17 17 == Objects, measurements, averages == … … 23 23 * '''Average tables''' know which measurements belong to the same objects, and record the average value, scatter, and error in the mean of the same object over different epochs, for each filter. They also record the proper motion and parrallax (if it has been determined). 24 24 25 Both sets of tables, the links between them, and derived quantities are created or computed by a set of commands outside of dvo ( <code>addstar, relphot, relastro</code>). Once you start dvo, everything you need should already be there...25 Both sets of tables, the links between them, and derived quantities are created or computed by a set of commands outside of dvo (`addstar, relphot, relastro`). Once you start dvo, everything you need should already be there... 26 26 27 27 == photcodes == … … 45 45 == Startup == 46 46 47 {{{ 47 48 dvo -D CATDIR /path/to/catdir 49 }}} 48 50 49 51 e.g. in Heidelberg: 50 52 53 {{{ 51 54 dvo -D CATDIR /IPP/data/GPC1/flatcorr_20081029/catdir.flatcorr 55 #or for the GPC1 data overlapping SDSS and UKIDSS on stripe 82 56 dvo -D CATDIR /a773/jester/PS1/catdir.20090327 -D CAMERA gpc1 57 }}} 52 58 53 59 == Getting help == … … 55 61 Most dvo commands have a help text that can be read with 56 62 63 {{{ 57 64 help command 65 }}} 58 66 59 67 The dvo shell allows tab completion of commands and filenames. … … 61 69 Most commands will also com/explain what they expect if called without arguments. 62 70 63 == Setting the <code>region</code>==71 == Setting the `region` == 64 72 65 Set the region for plotting and plot a coordinate grid: 73 {{{ 74 # for the flatcorr catdir 75 76 Set the region for plotting and plot a coordinate grid: 66 77 region 314.7428 37.1718 3 67 78 cgrid 79 #Set the region for catalog extraction: 80 skyregion 310 320 33 40 68 81 69 Set the region for catalog extraction: 70 skyregion 310 320 33 40 82 # for the 20090327 catdir 83 region 60 0 5 84 cgrid 85 skyregion 55 65 -2 2 86 }}} 71 87 72 88 == Loading data == … … 75 91 images 76 92 77 Extracting average quantities into vectors (similar to those in sm, or arrays in IDL or C etc.) is done via <code>avextract</code>; from the currently defined region by giving the <code>-region</code>argument:93 Extracting average quantities into vectors (similar to those in sm, or arrays in IDL or C etc.) is done via `avextract`; from the currently defined region by giving the `-region` argument: 78 94 avextract -region RA DEC g r i y 79 95 [... takes a while for big regions with lots of measurements ...] … … 84 100 no -region or -skyregion command # use previously defined skyregion 85 101 86 However, with the <code>-region</code> setting, the output list does not actually seem to be affected by changing the <code>region</code>. I.e. better use the <code>skyregion</code>variant!102 However, with the `-region` setting, the output list does not actually seem to be affected by changing the `region`. I.e. better use the `skyregion` variant! 87 103 88 Also note that there is only ever '''one''' active skyregion, ie. <code>avextract -skyregion</code> changes the skyregion in the same way as the <code>skyregion</code>command. You can see the currently active one with the104 Also note that there is only ever '''one''' active skyregion, ie. `avextract -skyregion` changes the skyregion in the same way as the `skyregion` command. You can see the currently active one with the 89 105 skyregion 90 106 command. 91 107 92 In addition to the quantities themselves, there is both an uncertainty and scatter; I think, usually the scatter is reported in the <code>:err</code> version of quantities; for RA and DEC, the error is in dRA, dDEC (see <code>avextract --help fields</code>:108 In addition to the quantities themselves, there is both an uncertainty and scatter; I think, usually the scatter is reported in the `:err` version of quantities; for RA and DEC, the error is in dRA, dDEC (see `avextract --help fields`: 93 109 avextract -region RA dRA DEC dDEC g g:err r r:err i i:err y y:err 94 110 … … 98 114 vectors 99 115 100 There are two more <code>extract</code>commands:101 * <code>mextract</code>extracts measurements; however, one can't compute colours from these (e.g.) because they are returned without any notion of which entry in the vector belongs to which object102 * <code>mmextract</code>extracts pairs of measurements belonging to the '''same''' object116 There are two more `extract` commands: 117 * `mextract` extracts measurements; however, one can't compute colours from these (e.g.) because they are returned without any notion of which entry in the vector belongs to which object 118 * `mmextract` extracts pairs of measurements belonging to the '''same''' object 103 119 104 120 == Searching == … … 106 122 === Restricting output of avextract etc. to interesting objects === 107 123 108 The <code>avextract</code>, <code>mextract</code> and <code>mmextract</code> commands allow restricting the rows that are returned by adding a SQL-like <code>where</code>clause:124 The `avextract`, `mextract` and `mmextract` commands allow restricting the rows that are returned by adding a SQL-like `where` clause: 109 125 avextract -region RA DEC g r i y where g-r < 0 110 126 … … 128 144 plot gr r 129 145 130 To plot things in sky coordinates, use <code>cplot</code>:146 To plot things in sky coordinates, use `cplot`: 131 147 cplot RA DEC 132 148 … … 140 156 addstar -D CAMERA gpc1 -D CATDIR /disk1/martin/GPC1/M31_Nov2008_mgc/catdir -accept-astrom ../47074/chip/o4776g0144o.47074.ch.11260.XY11.cmf 141 157 # I think relphot then needs to be run like so: 158 # If you add more images, add -update to the addstar arguments 159 # and then when all the addstars are finished, run one more addstar 160 # to resort the catalog: 142 161 addstar -D CATDIR . -D CAMERA gpc1 -resort 143 relphot -D CATDIR . -D CAMERA gpc1 -averages 162 relphot -D CATDIR . -D CAMERA gpc1 -averages -update 144 163 }}} 145 164 If you have gpc1 as your default camera in your ~/.ptolemyrc, you can omit the -D CAMERA gpc1.
