I do not know how to use setVertexBuffer

beginners
#1

header

	ofBufferObject PosBuff;
	ofVbo ObjsVbo;
    float vert[3*4];//This contains vertex information of a rectangle

setup

	PosBuff.allocate();
	PosBuff.setData(sizeof(float)*3*4,vert,GL_DYNAMIC_DRAW);
	
	ObjsVbo.setVertexBuffer(PosBuff,3,sizeof(float)*3,0);

draw

	ObjsVbo.draw(GL_POINTS,0,4);

This will not work properly.Please Help Me!!