[ci skip] Add minimal matplotlib script to display aggredated observations

docs/tutorials/basic_example.rst

@@ -97,3 +97,9 @@ Running the executable also created a folder with a name composed of YOUCOMPUTER
 
 
 The file ``samples.dat`` contains the coordinates of the samples that have been evaluated during each iteration, while the file ``aggregated_observations.dat`` contains the corresponding observed values. 
+
+If you want to display the different observations in a graph, you can the python script ``print_aggregated_observations.py``.
+For instance, from the root of limbo you can run ::
+  python src/tutorials/print_aggregated_observations.py YOUCOMPUTERHOSTNAME-DATE-HOUR-PID/aggregated_observations.dat
+
+

src/tutorials/print_aggregated_observations.py

+# this will load numpy for us
+import matplotlib.pyplot as plt
+import numpy as np
+import sys
+
+if(len(sys.argv)<2):
+    print("ERROR : Please provide path to the aggregated_observations.dat file.")
+    quit()
+    
+# Load and process data
+data = np.loadtxt(sys.argv[1],skiprows=1)
+x = data[:,0]
+y = data[:,1]
+min_y=np.min(y)
+max_y=np.max(y)
+rand_init_x = x[x==-1]
+rand_init_y = y[x==-1]
+
+y = y[x!=-1]
+x = x[x!=-1]
+
+# set vertical limit
+plt.ylim(min_y-0.1*np.abs(max_y-min_y), max_y+0.1*np.abs(max_y-min_y))
+
+# plot random initilization and observations
+rand_init = plt.plot(rand_init_x, rand_init_y,'g^', label='Random Initialization')
+observations = plt.plot(x, y,'bo',label = 'observations')
+plt.xlabel('Iterations')
+plt.ylabel('Observations')
+plt.title('Limbo')
+plt.legend(bbox_to_anchor=(1.05, 1), loc=2, borderaxespad=0.)
+plt.show()