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Example QDP file

A more complicated example than the standard case is when plotting with multiple models which have multiple components. For example, if creating a background model with NICER's SCORPEON tools, and then applying an absorbed powerlaw, the models might look like: 

  XSPEC>show param
 
  Parameters defined:
  ========================================================================
  Model TBabs<1>*powerlaw<2> Source No.: 1   Active/On
  Model Model Component  Parameter  Unit     Value
   par  comp
     1    1   TBabs      nH         10^22    1.34000E-02  +/-  0.0          
     2    2   powerlaw   PhoIndex            1.00000      +/-  0.0          
     3    2   powerlaw   norm                1.00000      +/-  0.0          
  ________________________________________________________________________
   
  ========================================================================
  Model nxb:niscorpv23_nxb<1> + niscorpv23_noise<2> Source No.: 99   Active/On
  Model Model Component  Parameter  Unit     Value
   par  comp
     1    1   niscorpv23_nxbthresh_offset       1.83993E-03  frozen
     2    1   niscorpv23_nxbbatch1_frac         0.940000     frozen
     3    1   niscorpv23_nxbcon_norm            47.0000      frozen
     4    1   niscorpv23_nxbcor_norm            9.08792      +/-  0.0          
     5    1   niscorpv23_nxbtrel_norm           11.7779      +/-  0.0          
     6    1   niscorpv23_nxbleel_norm           0.0          +/-  0.0          
     7    1   niscorpv23_nxbprel_norm           0.0          frozen
     8    1   niscorpv23_nxbsaa_norm            0.0          frozen
     9    1   niscorpv23_nxbnorm                1.00000      frozen
    10    2   niscorpv23_noisenoise_ecent       0.108755     frozen
    11    2   niscorpv23_noisenoise_sigma       2.68142E-02  frozen
    12    2   niscorpv23_noisenorm              246.573      +/-  0.0          
  ________________________________________________________________________
   
  ========================================================================
  Model sky:niscorpv23_sky<1> + niscorpv23_swcx<2> Source No.: 98   Active/On
  Model Model Component  Parameter  Unit     Value
   par  comp
     1    1   niscorpv23_skygal_nh              1.33731E-02  frozen
     2    1   niscorpv23_skycxb_ind             1.45000      frozen
     3    1   niscorpv23_skycxb_norm            10.9100      frozen
     4    1   niscorpv23_skyhalo_kT             0.225000     frozen
     5    1   niscorpv23_skyhalo_abund          0.300000     frozen
     6    1   niscorpv23_skyhalo_em             6.83000E-03  +/-  0.0          
     7    1   niscorpv23_skylhb_kT              9.90000E-02  frozen
     8    1   niscorpv23_skylhb_em              3.70000E-03  +/-  0.0          
     9    1   niscorpv23_skynorm                1.00000      frozen
    10    2   niscorpv23_swcxswcx_sigma         0.0          frozen
    11    2   niscorpv23_swcxok_norm            0.0          frozen
    12    2   niscorpv23_swcxovii_norm          0.0          frozen
    13    2   niscorpv23_swcxoviii_norm         0.0          frozen
    14    2   niscorpv23_swcxneix_norm          0.0          frozen
    15    2   niscorpv23_swcxnorm               1.00000      frozen
  ________________________________________________________________________

SCORPEON produced two models (nxb and sky) with two components each. After calling wdata, the resulting qdp file will have 12 columns:

  1. x-axis value (energy or wavelength)
  2. x-axis error
  3. y-axis value for the spectral data point
  4. y-axis error for spectral data point
  5. y-axis value for the sum of all models
  6. y-axis value for the tbabs*powerlaw model
  7. y-axis value for the nxb model
  8. y-axis value for the sky model
  9. y-axis value for the nxb additive component 1
  10. y-axis value for the nxb additive component 2
  11. y-axis value for the sky additive component 1
  12. y-axis value for the sky additive component 2

Note that array values can also be retrieved with tclout plot or with PyXspec's PlotManager class.