Michael Mayer / gammalib

Commit de69fbab0589793a28d26edd15e705cc18aa991c

Authored by Christoph Deil
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Minor changes to quickstart.rst

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... ... @@ -9,26 +9,24 @@ verify that the Python interfaces workes correctly. You do this by
9 9 typing::
10 10  
11 11 >>> from gammalib import *
12   - >>>
13 12  
14 13 If everything works fine you should just get a new Python prompt after
15 14 importing GammaLib. If you get an error message, make sure that you've
16 15 setup correctly the GammaLib environment. You basically need the
17   -PYTHONPATH variable set to GammaLib's Python site-package, and you also
  16 +``PYTHONPATH`` variable set to GammaLib's Python site-package, and you also
18 17 have to make sure that GammaLib and any dependent library (cfitsio,
19 18 readline, ncurses) is in the library load path (eventually you may need
20   -to adjust LD\_LIBRARY\_PATH). This is all done automatically if you set
  19 +to adjust ``LD_LIBRARY_PATH``). This is all done automatically if you set
21 20 up the environment as described
22 21 `here <installation.html#Setting_up_your_environment>`_.
23 22  
24 23 Now try::
25 24  
26   - >>> models=GModels()
27   - >>> print models
  25 + >>> models = GModels()
  26 + >>> print(models)
28 27 === GModels ===
29 28 Number of models ..........: 0
30 29 Number of parameters ......: 0
31   - >>>
32 30  
33 31 You just alloacted your first GammaLib object, which is an empty model
34 32 container.
... ... @@ -38,61 +36,61 @@ Now let&#39;s append a model to this container. For this, type::
38 36 >>> pos = GSkyDir()
39 37 >>> pos.radec_deg(83.6331, 22.0145)
40 38 >>> spatial = GModelSpatialPointSource(pos)
41   - >>> spectral = GModelSpectralPlaw(1.0, -2.0)
  39 + >>> spectral = GModelSpectralPlaw(1.0, -2.0, GEnergy(100, 'MeV'))
42 40 >>> model = GModelSky(spatial, spectral)
43 41 >>> models.append(model)
44   - >>> print models
  42 + >>> print(models)
45 43 === GModels ===
46   - Number of models ..........: 1
47   - Number of parameters ......: 6
  44 + Number of models ..........: 1
  45 + Number of parameters ......: 6
48 46 === GModelSky ===
49   - Name ......................:
50   - Instruments ...............: all
51   - Model type ................: "SkyDirFunction" * "PowerLaw" * "Constant"
52   - Number of parameters ......: 6
53   - Number of spatial par's ...: 2
54   - RA .......................: 83.6331 deg (fixed,scale=1)
55   - DEC ......................: 22.0145 deg (fixed,scale=1)
56   - Number of spectral par's ..: 3
57   - Prefactor ................: 1 +/- 0 [0,infty[ ph/cm2/s/MeV (free,scale=1,gradient)
58   - Index ....................: -2 +/- 0 [-10,10] (free,scale=1,gradient)
59   - PivotEnergy ..............: 100 MeV (fixed,scale=1,gradient)
60   - Number of temporal par's ..: 1
61   - Constant .................: 1 (relative value)
62   - (fixed,scale=1,gradient)
63   - >>>
  47 + Name ......................:
  48 + Instruments ...............: all
  49 + Instrument scale factors ..: unity
  50 + Observation identifiers ...: all
  51 + Model type ................: PointSource
  52 + Model components ..........: "SkyDirFunction" * "PowerLaw" * "Constant"
  53 + Number of parameters ......: 6
  54 + Number of spatial par's ...: 2
  55 + RA .......................: 83.6331 deg (fixed,scale=1)
  56 + DEC ......................: 22.0145 deg (fixed,scale=1)
  57 + Number of spectral par's ..: 3
  58 + Prefactor ................: 1 +/- 0 [0,infty[ ph/cm2/s/MeV (free,scale=1,gradient)
  59 + Index ....................: -2 +/- 0 [10,-10] (free,scale=-2,gradient)
  60 + PivotEnergy ..............: 100 MeV (fixed,scale=100,gradient)
  61 + Number of temporal par's ..: 1
  62 + Constant .................: 1 (relative value) (fixed,scale=1,gradient)
64 63  
65 64 With this sequence of commands you first defined a sky direction in
66   -celestial coordinates using GSkyDir. You may easily recognise that this
  65 +celestial coordinates using ``GSkyDir``. You may easily recognise that this
67 66 is the position of the Crab. You then used this position to define the
68   -spatial component of a sky model using GModelSpatialPtsrc. As the name
  67 +spatial component of a sky model using ``GModelSpatialPointSource``. As the name
69 68 suggests, the spatial component is a point source. Next, you defined the
70   -spectral component using GModelSpactralPlaw: a power law with
  69 +spectral component using ``GModelSpactralPlaw``: a power law with
71 70 normalisation of 1 and index of -2. Then, you combined the spatial and
72   -spectral components in a point source model using GModelPointSource. And
  71 +spectral components in a point source model using ``GModelSky``. And
73 72 finally you appended the point source to the model container allocated
74 73 previously using the append method. When you then print the model
75 74 container you see that is contains now one model with 6 parameters.
76   -Among them, you find the specified source position (parameters RA and
77   -DEC), the power law normalisation (parameter Prefactor) and the spectral
78   -index (parameter Index). In addition, the reference energy for the
79   -normalisation has been set automatically to 100 MeV (parameter
80   -PivotEnergy) and the temporal component has been set by default to a
81   -constant (parameter Constant).
  75 +Among them, you find the specified source position (parameters ``RA`` and
  76 +``DEC``), the power law normalisation (parameter ``Prefactor``) and the spectral
  77 +index (parameter ``Index``). In addition, the reference energy for the
  78 +normalisation has been set to 100 MeV (parameter ``PivotEnergy``)
  79 +and the temporal component has been set by default to a constant (parameter ``Constant``).
82 80  
83 81 Suppose you want to change one of these parameters, such as the
84   -PivotEnergy that you want to set to 1 TeV. This can be done using::
  82 +``PivotEnergy`` that you want to set to 1 TeV. This can be done using::
85 83  
86   - >>> models[0]['PivotEnergy'].value(1.0e6)
87   - >>> print models
  84 + >>> models[0]['PivotEnergy'].value(1e6)
  85 + >>> print(models)
88 86 ...
89   - PivotEnergy ..............: 1e+06 MeV (fixed,scale=1,gradient)
  87 + PivotEnergy ..............: 1e+06 MeV (fixed,scale=100,gradient)
90 88 ...
91 89  
92 90 As the units are MeV, we had to specify a value of 1e6 to set the
93 91 reference energy to 1 TeV. We did this by accessing the first model in
94 92 the container using ``models[0]`` (counting in GammaLib always starts from
95   -0). Then we addressed the PivotEnergy parameter by specifying
  93 +0). Then we addressed the ``PivotEnergy`` parameter by specifying
96 94 ``['PivotEnergy']``. And finally we called the value method that sets the
97 95 value of a particular parameter.
98 96  
... ... @@ -100,12 +98,11 @@ After all this hard work, you may save your model into a XML file by
100 98 typing::
101 99  
102 100 >>> models.save('test.xml')
103   - >>>
104 101  
105 102 and you can load it from an XML file in memory using::
106 103  
107   - >>> newmodels=GModels('test.xml')
108   - >>> print newmodels
  104 + >>> new_models = GModels('test.xml')
  105 + >>> print(new_models)
109 106  
110 107 The last print command is to convince yourself that the models have been
111 108 loaded properly.
... ...