--- /dev/null
+/* Copyright 2002 by Jeffrey Chang. All rights reserved.
+ * This code is part of the Biopython distribution and governed by its
+ * license. Please see the LICENSE file that should have been included
+ * as part of this package.
+ *
+ * csupport.c
+ * Created 27 January 2002
+ *
+ * Miscellaneous useful C functions not to be exported as a python
+ * module.
+ *
+ */
+
+#include "Python.h"
+
+
+/* Return a PyNumber as a double.
+ * Raises a TypeError if I can't do it.
+ */
+double PyNumber_AsDouble(PyObject *py_num)
+{
+ double val;
+ PyObject *floatobj;
+
+ if((floatobj = PyNumber_Float(py_num)) == NULL)
+ return(0.0);
+ val = PyFloat_AsDouble(floatobj);
+ Py_DECREF(floatobj);
+ return val;
+}