code: def _ppoints(n, a=0.5):
      """
      Ordinates For Probability Plotting.
  
      Numpy analogue or `R`'s `ppoints` function.
  
      Parameters
      ----------
      n : int
          Number of points generated
      a : float
          Offset fraction (typically between 0 and 1)
  
      Returns
      -------
      p : array
          Sequence of probabilities at which to evaluate the inverse
          distribution.
      """
      a = 3 / 8 if n <= 10 else 0.5
      return (np.arange(n) + 1 - a) / (n + 1 - 2 * a)
  
file_path: pingouin/pingouin/plotting.py
imports: import numpy
  import pandas
  import seaborn
  from scipy import stats
  import matplotlib.pyplot
  import matplotlib.transforms
label_desc: Use image node_id 2 for calling a global function with example usage: _ppoints(n, a) and returns: unknown