TIMP: tree impurity metric

git-svn-id: https://slps.svn.sourceforge.net/svnroot/slps@934 ab42f6e0-554d-0410-b580-99e487e6eeb2

topics/investigation/structural/testperform

@@ -7,4 +7,5 @@ echo [Test Case] `basename $1`
 ./rlev.py $1 >> $1.out || exit -1
 ./nlev.py $1 >> $1.out || exit -1
 ./hei.py $1 >> $1.out || exit -1
+./timp.py $1 >> $1.out || exit -1
 diff $1.out $1.baseline || exit -1

topics/investigation/structural/tests/antlr.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+44.5

topics/investigation/structural/tests/dcg.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+28.6

topics/investigation/structural/tests/ecore.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+67.4

topics/investigation/structural/tests/ecore2.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+48.6

topics/investigation/structural/tests/fl_ldf.bgf.baseline

@@ -4,3 +4,4 @@
 0
 0
 2
+15.0

topics/investigation/structural/tests/impl1.bgf.baseline

@@ -4,3 +4,4 @@
 20
 20
 22
+37.7

topics/investigation/structural/tests/impl2.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 9
+59.1

topics/investigation/structural/tests/impl3.bgf.baseline

@@ -4,3 +4,4 @@
 2
 2
 8
+71.8

topics/investigation/structural/tests/jaxb.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 2
+16.4

topics/investigation/structural/tests/ldf.bgf.baseline

@@ -4,3 +4,4 @@
 0
 0
 2
+15.0

topics/investigation/structural/tests/om.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 2
+21.1

topics/investigation/structural/tests/read1.bgf.baseline

@@ -4,3 +4,4 @@
 26
 26
 22
+31.9

topics/investigation/structural/tests/read2.bgf.baseline

@@ -4,3 +4,4 @@
 21
 21
 13
+56.8

topics/investigation/structural/tests/read3.bgf.baseline

@@ -4,3 +4,4 @@
 19
 19
 14
+58.7

topics/investigation/structural/tests/sdf.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+21.4

topics/investigation/structural/tests/txl.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+21.4

topics/investigation/structural/tests/xml.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+45.6

topics/investigation/structural/tests/xsd.bgf.baseline

@@ -4,3 +4,4 @@
 1
 1
 3
+45.6

topics/investigation/structural/timp.py

@@ -0,0 +1,26 @@
+#!/usr/local/bin/python
+# -*- coding: utf-8 -*-
+import sys
+import levels
+sys.path.append('../../../shared/python')
+import BGF
+
+if __name__ == "__main__":
+	if len(sys.argv) != 2:
+		print 'This tool calculates a TIMP metric for any given BGF grammar.'
+		print 'Usage:'
+		print '      '+sys.argv[0]+' <bgf-input>'
+		sys.exit(1)
+	bgf = BGF.Grammar()
+	bgf.parse(sys.argv[1])
+	cg = levels.getClosure(levels.getCallGraph(bgf))
+	n = len(cg)
+	e = sum(map(len,cg.values()))
+	# Power and Malloy made two mistakes:
+	# (1) the number of edges in a complete directed graph is n(n-1), not n(n-1)/2, as in a complete undirected graph!
+	# (2) we don't have to substract another 1 from the number of nonterminals to account for a start symbol
+	# To compute TIMP exactly as they intended to, run this:
+	# print '%.1f' % (100*2*(e-n+1)/(0.0+(n-1)*(n-2)))
+	# To run our fixed version, uncomment this:
+	print '%.1f' % (100*(e-n+1)/(0.0+n*(n-1)))
+	sys.exit(0)