Fix Exceptions to work with Python 2.6.

Fixes #361

--HG--
extra : convert_revision : svn%3A3ed01bd8-26fb-0310-9e4c-ca1a4053419f/networkx/trunk%401745

5 files changed, 17 insertions, 29 deletions

diff --git a/examples/algorithms/blockmodel.py b/examples/algorithms/blockmodel.py
index 2e4ff385..cf424926 100644
--- a/examples/algorithms/blockmodel.py
+++ b/examples/algorithms/blockmodel.py
@@ -49,10 +49,7 @@ def create_hc(G):
     return partition.values()
 
 if __name__ == '__main__':
-    try:
-        G=nx.read_edgelist("hartford_drug.edgelist")
-    except IOError:
-        raise "hartford_drug.edgelist not found"
+    G=nx.read_edgelist("hartford_drug.edgelist")
     
     # Extract largest connected component into graph H
     H=nx.connected_component_subgraphs(G)[0]
diff --git a/examples/graph/football.py b/examples/graph/football.py
index c5f3d0d7..95326814 100644
--- a/examples/graph/football.py
+++ b/examples/graph/football.py
@@ -19,20 +19,20 @@ __author__ = """Aric Hagberg (hagberg@lanl.gov)"""
 
 try:
     import pyparsing
-except ImportError:
-    raise "pyparsing not found: install http://pyparsing.wikispaces.com/"
+except ImportError,e:
+    raise ImportError(str(e)+". Check http://pyparsing.wikispaces.com/")
     
 from networkx import *
 
 url="http://www-personal.umich.edu/~mejn/netdata/football.zip"
 
-import urllib                                       
+import urllib
 import StringIO
 import zipfile
 
 sock = urllib.urlopen(url)  # open URL
 s=StringIO.StringIO(sock.read()) # read into StringIO "file"
-sock.close()                                        
+sock.close()
 
 zf = zipfile.ZipFile(s) # zipfile object
 txt=zf.read('football.txt') # read info file
diff --git a/examples/graph/knuth_miles.py b/examples/graph/knuth_miles.py
index 8cd75891..4c5b50e9 100644
--- a/examples/graph/knuth_miles.py
+++ b/examples/graph/knuth_miles.py
@@ -35,13 +35,10 @@ def miles_graph():
     """
     # open file miles_dat.txt.gz (or miles_dat.txt)
     try:
-        try:
-            import gzip
-            fh = gzip.open('knuth_miles.txt.gz','r')
-        except:
-            fh=open("knuth_miles.txt","r")
-    except IOError:
-        raise "File knuth_miles.txt not found."
+        import gzip
+        fh = gzip.open('knuth_miles.txt.gz','r')
+    except:
+        fh=open("knuth_miles.txt","r")
 
     G=nx.Graph()
     G.position={}
diff --git a/examples/graph/roget.py b/examples/graph/roget.py
index 01b2b7f6..a6d3526b 100644
--- a/examples/graph/roget.py
+++ b/examples/graph/roget.py
@@ -41,13 +41,10 @@ def roget_graph():
     """
     # open file roget_dat.txt.gz (or roget_dat.txt)
     try:
-        try:
-            import gzip
-            fh=gzip.open('roget_dat.txt.gz','r')
-        except:
-            fh=open("roget_dat.txt","r")
-    except IOError:
-        raise "File roget_dat.txt not found."
+        import gzip
+        fh=gzip.open('roget_dat.txt.gz','r')
+    except:
+        fh=open("roget_dat.txt","r")
 
     G=DiGraph()
 
diff --git a/examples/graph/words.py b/examples/graph/words.py
index 10900fcb..2f1660d2 100644
--- a/examples/graph/words.py
+++ b/examples/graph/words.py
@@ -60,13 +60,10 @@ def words_graph():
     import sys
     # open file words_dat.txt.gz (or words_dat.txt)
     try:
-        try:
-            import gzip
-            fh=gzip.open('words_dat.txt.gz','r')
-        except:
-            fh=open("words_dat.txt","r")
-    except IOError:
-        raise "File words_dat.txt not found."
+        import gzip
+        fh=gzip.open('words_dat.txt.gz','r')
+    except:
+        fh=open("words_dat.txt","r")
 
     G = Graph(name="words")
     sys.stderr.write("Loading words_dat.txt: ")