Handle gsl_permutation* in SWIG.

bct.h

@@ -164,6 +164,7 @@ namespace bct {
 	void gsl_free(gsl_vector* v);
 	void gsl_free(gsl_matrix* m);
 	void gsl_free(std::vector<gsl_matrix*>& m);
+	void gsl_free(gsl_permutation* p);
 	void init();
 	int number_of_edges_dir(const gsl_matrix* m);
 	int number_of_edges_und(const gsl_matrix* m);

bct_gsl.i

@@ -164,6 +164,7 @@ namespace bct {
 	void gsl_free(gsl_vector* v);
 	void gsl_free(gsl_matrix* m);
 	void gsl_free(std::vector<gsl_matrix*>& m);
+	void gsl_free(gsl_permutation* p);
 	void init();
 	int number_of_edges_dir(const gsl_matrix* m);
 	int number_of_edges_und(const gsl_matrix* m);
@@ -380,6 +381,8 @@ namespace matlab {
 PyObject* from_gsl(const gsl_vector* v);
 PyObject* from_gsl(const gsl_matrix* m);
 PyObject* from_gsl(const std::vector<gsl_matrix*>& m);
+PyObject* from_gsl(const gsl_permutation* p);
 gsl_vector* to_gslv(PyObject* list);
 gsl_matrix* to_gslm(PyObject* list);
 std::vector<gsl_matrix*> to_gsl3dm(PyObject* list);
+gsl_permutation* to_gslp(PyObject* list);

bct_py.i

@@ -26,6 +26,11 @@
 %typemap(freearg) std::vector<gsl_matrix*> { bct::gsl_free($1); }
 %typemap(out) std::vector<gsl_matrix*> { %append_output(from_gsl($1)); bct::gsl_free($1); }
 
+%typemap(typecheck) gsl_permutation* { $1 = is_gslp($input) ? 1 : 0; }
+%typemap(in) gsl_permutation* { $1 = to_gslp($input); }
+%typemap(freearg) gsl_permutation* { bct::gsl_free($1); }
+%typemap(out) gsl_permutation* { %append_output(from_gsl($1)); bct::gsl_free($1); }
+
 %typemap(in, numinputs = 0) gsl_vector** (gsl_vector* temp) { $1 = &temp; }
 %typemap(argout) gsl_vector** { %append_output(from_gsl(*$1)); bct::gsl_free(*$1); }
 

swig.i

@@ -1,6 +1,9 @@
 %{
+	#include <cmath>
 	#include <gsl/gsl_matrix.h>
+	#include <gsl/gsl_permutation.h>
 	#include <gsl/gsl_vector.h>
+	#include <limits>
 	#include <Python.h>
 	#include <vector>
 
@@ -43,6 +46,35 @@
 		return is_ndim_list(object, 3);
 	}
 
+	/*
+	 * Checks if a PyObject* can be converted to a gsl_permutation*.
+	 */
+	bool is_gslp(PyObject* object) {
+		if (!is_ndim_list(object, 1)) {
+			return false;
+		}
+		int n = PyList_Size(object);
+		std::vector<bool> found(n, false);
+		for (int i = 0; i < n; i++) {
+			double value = PyFloat_AsDouble(PyList_GetItem(object, i));
+			if (value < 0.0) {
+				return false;
+			}
+			double int_part;
+			double frac_part = std::modf(value, &int_part);
+			if (frac_part > std::numeric_limits<double>::epsilon()) {
+				return false;
+			}
+			int index = (int)int_part;
+			if (index >= n || found[index]) {
+				return false;
+			} else {
+				found[index] = true;
+			}
+		}
+		return true;
+	}
+
 	/*
 	 * Converts a gsl_vector* to a Python list.
 	 */
@@ -95,6 +127,18 @@
 		return list;
 	}
 
+	/*
+	 * Converts a gsl_permutation* to a Python list.
+	 */
+	PyObject* from_gsl(const gsl_permutation* p) {
+		PyObject* list = PyList_New(p->size);
+		for (int i = 0; i < (int)p->size; i++) {
+			PyObject* value = PyFloat_FromDouble(gsl_permutation_get(p, i));
+			PyList_SetItem(list, i, value);
+		}
+		return list;
+	}
+
 	/*
 	 * Converts a Python list to a gsl_vector*.
 	 */
@@ -151,4 +195,21 @@
 		}
 		return m;
 	}
+
+	/*
+	 * Converts a Python list to a gsl_permutation*.
+	 */
+	gsl_permutation* to_gslp(PyObject* list) {
+		int n = PyList_Size(list);
+		gsl_permutation* p = gsl_permutation_alloc(n);
+		for (int i = 0; i < n; i++) {
+			p->data[i] = (int)PyFloat_AsDouble(PyList_GetItem(list, i));
+		}
+		if (gsl_permutation_valid(p) == 1) {
+			gsl_permutation_free(p);
+			return NULL;
+		} else {
+			return p;
+		}
+	}
 %}

utility.cpp

@@ -1,6 +1,7 @@
 #include "bct.h"
 #include <gsl/gsl_errno.h>
 #include <gsl/gsl_matrix.h>
+#include <gsl/gsl_permutation.h>
 #include <gsl/gsl_vector.h>
 #include <sstream>
 #include <string>
@@ -28,6 +29,7 @@ void bct::gsl_free(std::vector<gsl_matrix*>& m) {
 		}
 	}
 }
+void bct::gsl_free(gsl_permutation* p) { gsl_permutation_free(p); }
 
 /*
  * Initializes the BCT library for external use.