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scipy.signal.symiirorder2

# scipy.signal.symiirorder1

`scipy.signal.``symiirorder1`(input, c0, z1 {, precision}) → output

  Implement a smoothing IIR filter with mirror-symmetric boundary conditions using a cascade of first-order sections. The second section uses a reversed sequence. This implements a system with the following transfer function and mirror-symmetric boundary conditions:

                      c0
      H(z) = ---------------------
              (1-z1/z) (1 - z1 z)

  The resulting signal will have mirror symmetric boundary conditions as well.

  Parameters: | input : ndarray The input signal. c0, z1 : scalar Parameters in the transfer function. precision : Specifies the precision for calculating initial conditions of the recursive filter based on mirror-symmetric input.
  Returns: | output : ndarray The filtered signal.