Fixed some Flake8 warnings

src/seemps/analysis/chebyshev.py

@@ -3,7 +3,6 @@
 
 import numpy as np
 from scipy.fft import dct  # type: ignore
-from typing import Callable, Optional
 
 from .mesh import ChebyshevZerosInterval, Interval
 from .factories import mps_interval

src/seemps/analysis/cross.py

@@ -211,6 +211,10 @@ def random_initial_indices(
     return I_g
 
 
+def _ones(x):
+    return np.ones((x, 1), dtype=int)
+
+
 def sample_initial_indices(state: MPS) -> list[np.ndarray]:
     """
     Samples initial indices from a given MPS by performing a sweep of
@@ -233,7 +237,6 @@ def sample_initial_indices(state: MPS) -> list[np.ndarray]:
     I_s = [np.array([[0], [1]]) for _ in range(sites)]
     I_le = [np.array([], dtype=int)] * (sites + 1)
     I_g = [np.array([], dtype=int)] * (sites + 1)
-    _ones = lambda x: np.ones((x, 1), dtype=int)
 
     # Forward pass
     R = np.ones((1, 1))
@@ -274,7 +277,7 @@ def sample_tensor_fiber(
     i_s: np.ndarray,
     i_g: np.ndarray,
 ) -> np.ndarray:
-    """
+    r"""
     Samples the k-th tensor fiber of the underlying MPS representation
     of a function from a collection of multi-indices centered at a
     given site k. I.e, samples $A\left(J_{\le k-1}, i_k, J_{\g
@@ -306,7 +309,6 @@ def sample_tensor_fiber(
     fiber : np.ndarray
         The sampled tensor fiber.
     """
-    _ones = lambda x: np.ones((x, 1), dtype=int)
     r_le = i_le.shape[0] if i_le.size > 0 else 1
     r_g = i_g.shape[0] if i_g.size > 0 else 1
     s = i_s.shape[0]
@@ -474,7 +476,6 @@ def get_error(state: MPS):
 
     converged = False
     message = f"Maximum number of sweeps {cross_strategy.maxiter} reached"
-    _ones = lambda x: np.ones((x, 1), dtype=int)
 
     for sweep in range(cross_strategy.maxiter):
         start_time = perf_counter()

src/seemps/optimization/descent.py

@@ -108,8 +108,9 @@ def gradient_descent(
         converged=False,
         message=f"Maximum number of iterations {maxiter} reached",
     )
+    weights: Any = []
     for step in range(maxiter + 1):
-        if step:
+        if step > 0:
             state = simplify(
                 MPSSum(weights, [state, H_state]),  # type: ignore
                 strategy=normalization_strategy,

src/seemps/state/_contractions.py

@@ -24,7 +24,6 @@ def _contract_last_and_first2(A: NDArray, B: NDArray) -> NDArray:
 
 try:
     from .core import _contract_last_and_first, _contract_nrjl_ijk_klm
-except:
-    raise Exception()
+except ImportError:
     _contract_last_and_first = _contract_last_and_first2
     _contract_nrjl_ijk_klm = _contract_nrjl_ijk_klm2