111

159-2.py

@@ -1,6 +1,7 @@
 import math
 import matplotlib.pyplot as plt
 
+#把原函数换成题干的形式########################
 def fx(x):
     return math.exp(x)-math.sin(x)
 
@@ -25,7 +26,7 @@ def DrawGraph(a, b, stepper):
     plt.show()
     return x, y
 
-
+#把范围改成题干的形式#######################
 if __name__ == "__main__":
     a = -2*math.pi
     b = math.pi

159-5.py

@@ -1,6 +1,6 @@
 import math
 
-
+#原函数和导数改成题干的形式#####################
 def f1(x):
     return x**2 + 10*math.cos(x)
 
@@ -17,12 +17,14 @@ def df2(x):
 # 牛顿方法求解方程
 def NewtonSolve(fx, dfx, x0, err, N0):
     count = 0
+    print(f"k={count}, x0={x0}")
     x1 = x0 + 1 + err
     while abs(x1 - x0) > err or abs(fx(x1)) > err: # 添加条件修正根误差太大的问题
         if abs(dfx(x1)) < 1e-10:
             return None, 0
         x1 = x0 - fx(x0) / dfx(x0)
         count += 1
+        print(f"k={count}, x{count}={x1},x1-x0={abs(x1-x0)}")
         if count > N0:
             return None, -1
         x0 = x1
@@ -41,6 +43,7 @@ if __name__ == "__main__":
     err = 1e-5
     N0 = 100
 
+#把初始值换成题干形式###############
     x0 = 1.6
     result,status = NewtonSolve(f1, df1, x0, err,N0)
     if status == 1:
@@ -51,7 +54,7 @@ if __name__ == "__main__":
         print("f1导数为0，无法收敛")
 
 
-    x0 = FindRootZone(f2, -5, 5, 0.01)
+    x0 = FindRootZone(f2, -5, 5, 0.01) # 查找f2的根区间与步长
     result, status = NewtonSolve(f2, df2, x0, err,N0)
     if status == 1:
         print(f"f2收敛 解为: {result}")

159-6.py

@@ -1,6 +1,6 @@
 import math
 
-
+#把函数改成题干的形式#####################
 def f(x):
     return x**2 - 30
 
@@ -10,12 +10,14 @@ def df(x):
 # 牛顿方法求解方程
 def NewtonSolve(fx, dfx, x0, err, N0):
     count = 0
+    print(f"k={count}, x0={x0}")
     x1 = x0 + 1 + err
     while abs(x1 - x0) > err or abs(fx(x1)) > err: # 添加条件修正根误差太大的问题
         if abs(dfx(x1)) < 1e-10:
             return None, 0
         x1 = x0 - fx(x0) / dfx(x0)
         count += 1
+        print(f"k={count}, x{count}={x1},x1-x0={abs(x1-x0)}")
         if count > N0:
             return None, -1
         x0 = x1
@@ -34,6 +36,6 @@ if __name__ == "__main__":
     err = 1e-4
     N0 = 100
 
-    x0 = FindRootZone(f, 5, 6, 0.01)
+    x0 = FindRootZone(f, 5, 6, 0.1) # 查找f的根的区间与步长，改成题干对应的范围
     result,status = NewtonSolve(f, df, x0, err,N0)
     print(f"sqrt(30) = {result:.3f}")

160-11.py

@@ -17,11 +17,11 @@ def SecantSolve(fx, x0, x1, err=1e-10, N0=100):
         x1 = x2
     return x2,1
 
-
+#把精度要求改成题干要求的##########################
 if __name__ == "__main__":
     err = 1e-5
     N0 = 100
-
+##把初始函数和初始值改成题干要求的##########################
     x0 = 0.3
     x1 = 0.4
     fx = lambda x: x**4 - 3*x + 1

160-12.py

@@ -45,12 +45,12 @@ def MullerSolve(fx,x0,x1,x2,err1,err2,N):
         f2 = f3
         q = h1
 
-
+#精度要求#########################（152页）
 if __name__ == "__main__":
     err1 = 1e-5
     err2 = 1e-5
     N = 100
-
+##把初始函数和初始值改成题干要求的##########################
     x0 = 0.3
     x1 = 0.5
     x2 = 0.4