# 导入库
import numpy
from matplotlib import pyplot
import sympy
from sympy import pprint
# 建立方程
def f(x):
return numpy.abs(x-8)-numpy.abs(x-4)
x=sympy.symbols('x')
inequality=(sympy.Abs(x-8)-sympy.Abs(x-4)) >2
# 解方程
solution=sympy.solve(inequality,x)
# 输出结果
pprint(solution)
# 检测x值的范围
x=numpy.linspace(0,12,100)
# 找到对应的y值
y=f(x)
# 绘制图形
pyplot.plot(x,y)
pyplot.xlabel('x')
pyplot.ylabel('f(x)')
pyplot.title('Global f(x)=|x-8|-|x-4|')
pyplot.grid(True)
pyplot.show()