# Example 2: Making a GTC/triangle plot with Planck and WMAP data!¶

The full set of chains from the Planck 2015 release is available at http://pla.esac.esa.int/pla/#cosmology. You will want to download COM_CosmoParams_fullGrid_R2.00.tar.gz. Careful, that’s a huge file to download (3.6 GB)!

Extract everything into a directory, cd into that directory, and run this notebook.

%matplotlib inline
%config InlineBackend.figure_format = 'retina' # For mac users with Retina display

import numpy as np
from matplotlib import pyplot as plt
import pygtc


## Read in and format the data¶

WMAP, Planck = [],[]
for i in range(1,5):

# Copy all four chains into a single array
WMAPall = np.concatenate((WMAP[0],WMAP[1],WMAP[2],WMAP[3]))
Planckall = np.concatenate((Planck[0],Planck[1],Planck[2],Planck[3]))


## Select the parameters and make labels¶

In the chain directories, there are .paramnames files that allow you to find the parameters you are interested in.

WMAPplot = WMAPall[:,[2,3,4,5,6,7,9,15]]
Planckplot = Planckall[:,[2,3,4,5,6,7,23,29]]

# Labels, pyGTC supports Tex enclosed in $..$
params = ('$\Omega_\mathrm{b}h^2$',
'$\Omega_\mathrm{c}h^2$',
'$100\\theta_\mathrm{MC}$',
'$\\tau$',
'$\ln(10^{10}A_s)$',
'$n_s$','$H_0$',
'$\\sigma_8$')

chainLabels = ('$Planck$ (TT+lowTEB)','WMAP')


## Make the GTC!¶

Produce the plot and save it as Planck-vs-WMAP.pdf.

GTC = pygtc.plotGTC(chains=[Planckplot,WMAPplot],
weights=[Planckall[:,0],
WMAPall[:,0]],
paramNames=params,
chainLabels=chainLabels,
colorsOrder=('greens','blues'),
figureSize='APJ_page',
plotName='Planck-vs-WMAP.pdf')