[pre-commit.ci] auto fixes from pre-commit.com hooks

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python/taichi/linalg/matrixfree_cg.py

@@ -180,7 +180,7 @@ def MatrixFreeBICGSTAB(A, b, x, tol=1e-6, maxiter=5000, quiet=True):
     rho_1 = ti.field(dtype=solver_dtype)
     scalar_builder.place(alpha, beta, omega, rho, rho_1)
     scalar_snode_tree = scalar_builder.finalize()
-    
+
     @ti.kernel
     def init():
         for I in ti.grouped(x):
@@ -203,20 +203,20 @@ def reduce(p: ti.template(), q: ti.template()) -> solver_dtype:
         return result
 
     @ti.kernel
-    def copy(orig:ti.template(), dest:ti.template()):
+    def copy(orig: ti.template(), dest: ti.template()):
         for I in ti.grouped(orig):
             dest[I] = orig[I]
 
     @ti.kernel
     def update_p():
         for I in ti.grouped(p):
-            p[I] = r[I] + beta[None]*(p[I] - omega[None] * Ap[I])
+            p[I] = r[I] + beta[None] * (p[I] - omega[None] * Ap[I])
 
     @ti.kernel
     def update_phat():
         for I in ti.grouped(p_hat):
-            p_hat[I] = p[I]  
-            
+            p_hat[I] = p[I]
+
     @ti.kernel
     def update_s():
         for I in ti.grouped(s):
@@ -231,12 +231,12 @@ def update_shat():
     def update_x():
         for I in ti.grouped(x):
             x[I] += alpha[None] * p_hat[I] + omega[None] * s_hat[I]
-    
+
     @ti.kernel
     def update_r():
         for I in ti.grouped(r):
-            r[I] = s[I] - omega[None] * t[I]            
-            
+            r[I] = s[I] - omega[None] * t[I]
+
     def solve():
         init()
         initial_rTr = reduce(r, r)
@@ -245,7 +245,7 @@ def solve():
         for i in range(maxiter):
             rho[None] = reduce(r, r_tld)
             if rho[None] == 0.0:
-                print('>>> BICGSTAB failed because r@r_tld = 0.')
+                print(">>> BICGSTAB failed because r@r_tld = 0.")
                 break
             if i == 0:
                 copy(orig=r, dest=p)
@@ -262,20 +262,18 @@ def solve():
             copy(orig=Ashat, dest=t)
             omega_upper = reduce(t, s)
             omega_lower = reduce(t, t)
-            omega[None] = omega_upper / (omega_lower + 1e-16) if omega_lower == 0.0 \
-                else omega_upper / omega_lower
+            omega[None] = omega_upper / (omega_lower + 1e-16) if omega_lower == 0.0 else omega_upper / omega_lower
             update_x()
             update_r()
             rTr = reduce(r, r)
             if not quiet:
                 print(f">>> Iter = {i+1:4}, Residual = {sqrt(rTr):e}")
             if sqrt(rTr) < tol:
                 if not quiet:
-                    print(f'>>> BICGSTAB method converged at #iterations {i}')
+                    print(f">>> BICGSTAB method converged at #iterations {i}")
                 break
             rho_1[None] = rho[None]
-            
+
     solve()
     vector_fields_snode_tree.destroy()
     scalar_snode_tree.destroy()
-