code: function sinc(x) {
  
          // The value of sinc(0) is defined as 1
          if (x === 0)
              return 1;
  
          // Otherwise, normlized sinc(x) is sin(PI * x) / (PI * x)
          var piX = Math.PI * x;
          return Math.sin(piX) / piX;
  
      }
docs: The normalized sinc function. The normalized sinc function is defined as
  1 for x=0 and sin(PI * x) / (PI * x) for all other values of x.
  
  See: https://en.wikipedia.org/wiki/Sinc_function
  
  @private
  @param {Number} x
  The point at which the normalized sinc function should be computed.
  
  @returns {Number}
  The value of the normalized sinc function at x.