First commit

libsvm-3.36/tools/checkdata.py

@@ -0,0 +1,108 @@
+#!/usr/bin/env python
+
+#
+# A format checker for LIBSVM
+#
+
+#
+# Copyright (c) 2007, Rong-En Fan
+#
+# All rights reserved.
+#
+# This program is distributed under the same license of the LIBSVM package.
+#
+
+from sys import argv, exit
+import os.path
+
+def err(line_no, msg):
+    print("line {0}: {1}".format(line_no, msg))
+
+# works like float() but does not accept nan and inf
+def my_float(x):
+    if x.lower().find("nan") != -1 or x.lower().find("inf") != -1:
+        raise ValueError
+
+    return float(x)
+
+def main():
+    if len(argv) != 2:
+        print("Usage: {0} dataset".format(argv[0]))
+        exit(1)
+
+    dataset = argv[1]
+
+    if not os.path.exists(dataset):
+        print("dataset {0} not found".format(dataset))
+        exit(1)
+
+    line_no = 1
+    error_line_count = 0
+    for line in open(dataset, 'r'):
+        line_error = False
+
+        # each line must end with a newline character
+        if line[-1] != '\n':
+            err(line_no, "missing a newline character in the end")
+            line_error = True
+
+        nodes = line.split()
+
+        # check label
+        try:
+            label = nodes.pop(0)
+
+            if label.find(',') != -1:
+                # multi-label format
+                try:
+                    for l in label.split(','):
+                        l = my_float(l)
+                except:
+                    err(line_no, "label {0} is not a valid multi-label form".format(label))
+                    line_error = True
+            else:
+                try:
+                    label = my_float(label)
+                except:
+                    err(line_no, "label {0} is not a number".format(label))
+                    line_error = True
+        except:
+            err(line_no, "missing label, perhaps an empty line?")
+            line_error = True
+
+        # check features
+        prev_index = -1
+        for i in range(len(nodes)):
+            try:
+                (index, value) =  nodes[i].split(':')
+
+                index = int(index)
+                value = my_float(value)
+
+                # precomputed kernel's index starts from 0 and LIBSVM
+                # checks it. Hence, don't treat index 0 as an error.
+                if index < 0:
+                    err(line_no, "feature index must be positive; wrong feature {0}".format(nodes[i]))
+                    line_error = True
+                elif index <= prev_index:
+                    err(line_no, "feature indices must be in an ascending order, previous/current features {0} {1}".format(nodes[i-1], nodes[i]))
+                    line_error = True
+                prev_index = index
+            except:
+                err(line_no, "feature '{0}' not an <index>:<value> pair, <index> integer, <value> real number ".format(nodes[i]))
+                line_error = True
+
+        line_no += 1
+
+        if line_error:
+            error_line_count += 1
+
+    if error_line_count > 0:
+        print("Found {0} lines with error.".format(error_line_count))
+        return 1
+    else:
+        print("No error.")
+        return 0
+
+if __name__ == "__main__":
+    exit(main())