Why doesn't SharpGL draw a polygon when given a vector?

Question

OpenGL

//Есть массив координат(x1, y1, x2, y2, ...)
float[] data //...;

//Есть код отрисовки
 gl.Begin(SharpGL.Enumerations.BeginMode.Polygon);
                    gl.Vertex(data);
gl.End();

If you draw point by point (through a loop), then it works fine, but if you pass a vector (as in the code above), then nothing is drawn. When I worked with OpenGL through C ++, there were no such problems.