To simplify the diagram, is shown as a continuous function, even though the variables m and n are discrete. The mesh plot of the magnitude is a common way to visualize the Fourier transform. The peak at the center of the plot is , which is the sum of all the values in . The plot also shows that has more energy at high horizontal frequencies than at high vertical frequencies. This reflects the fact that horizontal cross sections of are narrow pulses, while vertical cross sections are broad pulses.
Narrow pulses have more high-frequency content than broad pulses.
Examples of the Fourier transform for other simple shapes are shown below.