Fixed errata in documentation

pynkowski/data/array.py

@@ -78,6 +78,10 @@ class DataArray(DataField):
  
  second_der : np.array or None
  Second **covariant** derivatives of the field in an orthonormal basis of the space. Same structure as `field`, and shape `(dim*(dim+1)/2, field.shape)`.
+
+ spacing : float or np.array
+ Spacing between pixels (centres) in each dimension. If a float, the spacing is the same in all dimensions.
+ If an array, it must have the same length as the number of dimensions of the field.
  
  """
  def __init__(self, field, normalise=True, mask=None, spacing=1.):

pynkowski/data/so3data.py

@@ -483,9 +483,12 @@ def get_second_der(self, lmax=None):
  """Compute the covariant second derivatives of the input Healpix scalar map. 
  It stores:
  
- - second covariant derivative wrt θθ in self.second_der[0]
- - second covariant derivative wrt ϕϕ in self.second_der[1]
- - second covariant derivative wrt θϕ in self.second_der[2]
+ - second covariant derivative wrt e₁e₁ in self.second_der[0]
+ - second covariant derivative wrt e₂e₂ in self.second_der[1]
+ - second covariant derivative wrt e₃e₃ in self.second_der[2]
+ - second covariant derivative wrt e₁e₂ in self.second_der[3]
+ - second covariant derivative wrt e₁e₃ in self.second_der[4]
+ - second covariant derivative wrt e₂e₃ in self.second_der[5]
 
  Parameters
  ----------