我的使用scipy的python代码抛出值错误

如何解决我的使用scipy的python代码抛出值错误

我有以下问题，并且已为其编写以下代码：

def prob6():
"""Time regular and sparse linear system solvers.

For varIoUs values of n,generate the (n**2,n**2) matrix A described of
prob5() and vector b of length n**2. Time how long it takes to solve the
system Ax = b with each of the following approaches:

    1. Convert A to CSR format and use scipy.sparse.linalg.spsolve()
    2. Convert A to a NumPy array and use scipy.linalg.solve().

In each experiment,only time how long it takes to solve the system (not
how long it takes to convert A to the appropriate format). Plot the system
size n**2 versus the execution times. As always,use log scales where
appropriate and use a legend to label each line.
"""
#raise NotImplementedError("Problem 6 Incomplete")

n = 2**np.arange(1,5)

time1 = []
time2 = []



for i in n:
    diagonals = [[1],[-4],[1]]
    offsets = [-1,1]
    B = (sparse.diags(diagonals,offsets,shape=(i,i)))
    A = sparse.block_diag(([B]*i))
    A.setdiag(1,i)
    A.setdiag(1,-i)
    A.setdiag(1,-i)
    print(A.toarray())
    b = np.random.random(i*i)
    Acsr = A.tocsr()
    start = time.time()
    Acsr_final = spla.spsolve(A,b)
    time1.append(time.time() - start)

for i in n:
    diagonals = [[1],-i)
    A.toarray()
    b = np.random.random(i*i)
    Anpa = np.squeeze(np.asarray(A))
    start = time.time()
    Anpa_final = sp.linalg.solve(A,b)
    time2.append(time.time() - start)

plt.loglog(n,time1,'m.-',lw=2,ms=15,label="time 1")
plt.loglog(n,time2,'g.-',label="time 2")
plt.legend()
plt.title("Times regular and sparse linear system solvers")
plt.xlabel("n",fontsize=14)
plt.ylabel("Seconds",fontsize=14)
plt.show()

prob6（）

它一直在第243行抛出以下ValueError，我似乎无法解决。我的scipy功能之一似乎有问题。我也不确定我所做的是否正确，因此这也可能使事情变得混乱。有人可以帮忙吗？

ValueError: Sparse matrices are not supported by this function. Perhaps one of the scipy.sparse.linalg functions would work instead.