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# numpy.unwrap

numpy.unwrap(p, discont=None, axis=-1, *, period=6.283185307179586)

  Unwrap by taking the complement of large deltas with respect to the period.

  This unwraps a signal p by changing elements which have an absolute difference from their predecessor of more than `max(discont, period/2)` to their period-complementary values.

  For the default case where period is \(2\pi\) and discont is \(\pi\), this unwraps a radian phase p such that adjacent differences are never greater than \(\pi\) by adding \(2k\pi\) for some integer \(k\).

  Parameters:
    p array_like

      Input array.

    discont float, optional

      Maximum discontinuity between values, default is `period/2`. Values below `period/2` are treated as if they were `period/2`. To have an effect different from the default, discont should be larger than `period/2`.

    axis int, optional

      Axis along which unwrap will operate, default is the last axis.

    period float, optional

      Size of the range over which the input wraps. By default, it is `2 pi`.

      Added in version 1.21.0.

  Returns:
    out ndarray

      Output array.

  See also

  `rad2deg`, `deg2rad`

  Notes

  If the discontinuity in p is smaller than `period/2`, but larger than discont, no unwrapping is done because taking the complement would only make the discontinuity larger.

  Examples

      >>> import numpy as np

      >>> phase = np.linspace(0, np.pi, num=5)
      >>> phase[3:] += np.pi
      >>> phase
      array([ 0.        ,  0.78539816,  1.57079633,  5.49778714,  6.28318531]) # may vary
      >>> np.unwrap(phase)
      array([ 0.        ,  0.78539816,  1.57079633, -0.78539816,  0.        ]) # may vary
      >>> np.unwrap([0, 1, 2, -1, 0], period=4)
      array([0, 1, 2, 3, 4])
      >>> np.unwrap([ 1, 2, 3, 4, 5, 6, 1, 2, 3], period=6)
      array([1, 2, 3, 4, 5, 6, 7, 8, 9])
      >>> np.unwrap([2, 3, 4, 5, 2, 3, 4, 5], period=4)
      array([2, 3, 4, 5, 6, 7, 8, 9])
      >>> phase_deg = np.mod(np.linspace(0 ,720, 19), 360) - 180
      >>> np.unwrap(phase_deg, period=360)
      array([-180., -140., -100.,  -60.,  -20.,   20.,   60.,  100.,  140.,
              180.,  220.,  260.,  300.,  340.,  380.,  420.,  460.,  500.,
              540.])

  This example plots the unwrapping of the wrapped input signal w. First generate w, then apply `unwrap` to get u.

      >>> t = np.linspace(0, 25, 801)
      >>> w = np.mod(1.5 * np.sin(1.1 * t + 0.26) * (1 - t / 6 + (t / 23) ** 3), 2.0) - 1
      >>> u = np.unwrap(w, period=2.0)

  Plot w and u.

      >>> import matplotlib.pyplot as plt
      >>> plt.plot(t, w, label='w (a signal wrapped to [-1, 1])')
      >>> plt.plot(t, u, linewidth=2.5, alpha=0.5, label='unwrap(w, period=2)')
      >>> plt.xlabel('t')
      >>> plt.grid(alpha=0.6)
      >>> plt.legend(framealpha=1, shadow=True)
      >>> plt.show()