21.5.3  Blackman window

The blackman_window command applies the Blackman window function to a sequence or its segment.

• blackman_window takes one mandatory argument and up to three optional arguments:
  • v, a real vector with length n.
  • Optionally, one of:
    • α, a real number (by default, α=0.16).
    • m,N ⟨,α⟩, a sequence of two integers and optionally a real number α (by default, m=0 and N=n).
• blackman_window returns the elementwise product of [v_m,v_m+1,…,v_m+N−1] and the vector w of length N defined by

  wk=

  1−α 2

  −

  1 2

  cos

  ⎛ ⎜ ⎜ ⎝

  2 k π N−1

  ⎞ ⎟ ⎟ ⎠

  +

  α 2

  cos

  ⎛ ⎜ ⎜ ⎝

  4 k π N−1

  ⎞ ⎟ ⎟ ⎠

  ,    k=0,1,…,N−1.

Example