Python fsolve查找函数的零，但也查找局部最小值/最大值。我只想画域[-3,5]上的零

下面是通过imgur显示的输出图

我想在域[-3,5]上绘制函数的所有零。但是，除了零之外，fsolve还为我提供了本地分钟和本地最大值：

import warnings
warnings.filterwarnings('ignore', 'The iteration is not making good progress')
import matplotlib.pyplot as plt
import numpy as np
import math
import time
from scipy.optimize import fsolve
#
#
# if using a jupyter notebook
%matplotlib inline
def f(x):
    return np.sin(3*math.pi*np.cos(2*math.pi*x) * np.sin(math.pi*x))
#
x0 = np.linspace(-3, 5, 40000, endpoint=True)
t = time.time()
q = np.zeros(np.shape(x0))
# print(len(x0))
for i in range(40000):
    q[i] = fsolve(f, x0[i], full_output=False)
ts = time.time() -t
print(ts)
qq = np.unique(q)
print(q)
AA = np.shape(qq)
print(AA)
plt.rcParams['figure.figsize'] = [15, 7]
xx = np.arange(-3,5,0.008)   # start,stop,step
def f(x):
    return np.sin(3*math.pi*np.cos(2*math.pi*x) * np.sin(math.pi*x))
plt.plot(xx,f(xx))
plt.plot(qq,f(qq),'ro')
plt.yticks(np.arange(min(f(xx)), max(f(xx))+1, 1.0))
plt.xlim(-3, 5)
plt.show()