code: def slope(X):
      """Numba slope function for a 1d numpy array.
  
      Parameters
      ----------
      X : 1d numpy array
          A 1d numpy array of values
  
      Returns
      -------
      slope : float
          The slope of the input array
      """
      sum_y = 0
      sum_x = 0
      sum_xx = 0
      sum_xy = 0
      for i in range(X.shape[0]):
          sum_y += X[i]
          sum_x += i
          sum_xx += i * i
          sum_xy += X[i] * i
      slope = sum_x * sum_y - X.shape[0] * sum_xy
      denom = sum_x * sum_x - X.shape[0] * sum_xx
      return 0 if denom == 0 else slope / denom
  
imports: from sktime.utils.validation._dependencies import _check_soft_dependencies
  import numpy
  import sktime.utils.numba.general
  from sktime.utils.numba.njit import njit
label_desc: Use image node_id 16 for calling a global function with example usage: slope(X) and returns: unknown