A novel 2D graphical representation of DNA sequences is introduced in this paper. DNA sequence is coded by assigning pyrimidine-purine to four real number pairs and using the content and position number as parameters. The presented method results in simpler characterizations and comparisons of DNA sequences. It has some important advantages: (A) it avoids loss of position information of A, T, C and G in DNA sequence; (B) normalized numerical coordinate of DNA sequences provide a straightforward comparison despite different lengths. The utility of the approach can be illustrated by the examination of similarities/dissimilarities among the coding sequences of the first exons of beta-globin genes of eleven different species.