Linted.

grext/fitting.py

@@ -5,14 +5,16 @@ import numpy as np
 
 def linear(vectors: List[np.ndarray], target: np.ndarray):
     """Simple least square minimization fitting."""
-    A = np.vstack(vectors).T
-    coefficients, _, _, _ = np.linalg.lstsq(A, target, rcond=None)
+    matrix = np.vstack(vectors).T
+    coefficients, _, _, _ = np.linalg.lstsq(matrix, target, rcond=None)
     return np.array(coefficients, dtype=np.float64)
 
 def quasi_time_reversible():
     """Time reversible least square minimization fitting."""
 
 def linear_combination(vectors: List[np.ndarray], coefficients: np.ndarray) -> np.ndarray:
+    """Given a set of vectors (or matrices) and the corresponding
+    coefficients, build their linear combination."""
     result = np.zeros(vectors[0].shape, dtype=np.float64)
     for coeff, vector in zip(coefficients, vectors):
         result += vector*coeff