ROOT sucks and the TApplication object created by PyROOT interprets

the contents of sys.argv whether you want it to or not.

A simple hack is to blank out sys.argv around the point where you
import ROOT.  As an additional requirement, you have to actually use
the ROOT module for something (even just looking up a class) in order
for the TApplication to be initialized, so you can't just replace
sys.argv with an empty array around the ROOT import.

To ensure this is always done correctly, all Chroma modules that need
ROOT should obtain it by:

from chroma.rootimport import ROOT

3 files changed, 14 insertions, 2 deletions

diff --git a/chroma/io/root.py b/chroma/io/root.py
index 55f7858..3fb7062 100644
--- a/chroma/io/root.py
+++ b/chroma/io/root.py
@@ -1,9 +1,10 @@
-import ROOT
 import os, os.path
 import shutil
 import numpy as np
 import chroma.event as event
 
+from chroma.rootimport import ROOT
+
 # Create .chroma directory if it doesn't exist
 chroma_dir = os.path.expanduser('~/.chroma')
 if not os.path.isdir(chroma_dir):
diff --git a/chroma/parabola.py b/chroma/parabola.py
index f4160fb..425f71b 100644
--- a/chroma/parabola.py
+++ b/chroma/parabola.py
@@ -1,7 +1,8 @@
 import numpy as np
 import uncertainties
 from uncertainties import unumpy
-import ROOT
+
+from chroma.rootimport import ROOT
 
 def build_design_matrix(x, y):
     y_invsigma = 1.0/unumpy.std_devs(y)
diff --git a/chroma/rootimport.py b/chroma/rootimport.py
new file mode 100644
index 0000000..6bcb6f6
--- /dev/null
+++ b/chroma/rootimport.py
@@ -0,0 +1,10 @@
+# TApplication is so incredibly annoying.
+# STOP SNOOPING THE ARGUMENT LIST AND PRINTING BOGUS HELP MESSAGES!! 
+import sys
+_argv = sys.argv
+sys.argv = []
+import ROOT
+# Have to do something with the module to get TApplication initialized
+ROOT.TObject # This just fetches the class and does nothing else
+sys.argv = _argv
+del _argv