The rectangular function $($or square$-$pulse$)$ is commonly used in signal processing applications. The Fourier transform of the rectangular function is the normalized sinc function given by:

$$

Write a function normsinc$$that returns $.$Your function must:

Calculate $$for each element of the input. If the input is a $1-$by$-4$vector$,$ the output is also a $1-$by$-4.$

Return the value $1$ when the input is $0,$ which is the limiting value of sinc$$as $.$

Two sample inputs are provided for you to test your code.