public static void plotFunction(Mesh mesh, Function fun, String fileName) { NodeList list = mesh.getNodeList(); int nNode = list.size(); Variable var = new Variable(); Vector v = new SparseVectorHashMap(nNode); for (int i = 1; i <= nNode; i++) { Node node = list.at(i); var.setIndex(node.globalIndex); var.set("x", node.coord(1)); var.set("y", node.coord(2)); v.set(i, fun.value(var)); } plotVector(mesh, v, fileName); }