class SPCore::NuttallWindow
Produces a Nuttall window of a given size (number of samples). For more info, see en.wikipedia.org/wiki/Window_function#Nuttall_window.2C_continuous_first_derivative.
Attributes
data[R]
Public Class Methods
new(size)
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# File lib/spcore/windows/nuttall_window.rb, line 6 def initialize size @data = Array.new(size) a0, a1, a2, a3 = 0.355768, 0.487396, 0.144232, 0.012604 size.times do |n| @data[n] = a0 - a1 * Math::cos((TWO_PI * n)/(size - 1)) + a2 * Math::cos((FOUR_PI * n)/(size - 1)) - a3 * Math::cos((SIX_PI * n)/(size - 1)) end end