Merge branch 'main' of https://gitea.pi5.lhye.work/lhye200/CalWay_Python

120-5.py

@@ -5,17 +5,9 @@ def fx(x):
         x = 1e-10  # Avoid division by zero
     return math.sin(x)/x
 
-
-
 def Romberg(a, b, err):
     t00 = (b-a)*(fx(a)+fx(b))/2
-    t01 = 0
-    t10 = 0
-    t11 = 0
-    t20 = 0
-    t21 = 0
-    t30 = 0
-    t31 = 0
+    t01 = t10 = t11 = t20 = t21 = t30 = t31 = 0
     k = 1
     while True:
         tmp = 0

159-2.py

@@ -0,0 +1,34 @@
+import math
+import matplotlib.pyplot as plt
+
+def fx(x):
+    return math.exp(x)-math.sin(x)
+
+def DrawGraph(a, b, stepper):
+    x = [a + (b-a)*i*stepper for i in range(int(1/stepper+1))]
+    y = [fx(i) for i in x]
+    plt.xlim(a-abs(b-a)*0.1, b+abs(b-a)*0.1)
+    plt.plot(x, y)
+    plt.axhline(0, color='black', lw=0.5, ls='-')
+    plt.axvline(a, color='red', lw=0.5, ls='--')
+    plt.axvline(b, color='red', lw=0.5, ls='--')
+    plt.text(a, y[0], f'({a:.5f},{y[0]:.5f})', fontsize=8, ha='left')
+    plt.text(b, y[-1], f'({b:.5f},{y[-1]:.5f})', fontsize=8, ha='right')
+    for i in range(len(x)-1):
+        if y[i] * y[i+1] < 0:
+            print(f"可能存在零点: ({x[i]:.5f},{y[i]:.5f})和({x[i+1]:.5f},{y[i+1]:.5f})之间")
+            plt.plot((x[i]+x[i+1])/2, (y[i]+y[i+1])/2, 'ro', markersize=3)
+    plt.title("Graph of f(x)")
+    plt.xlabel("x")
+    plt.ylabel("f(x)")
+    plt.show()
+    return x, y
+
+
+if __name__ == "__main__":
+    a = -2*math.pi
+    b = math.pi
+    step = 0.00001
+    print(f"边界点: {a}, {b}")
+    print(f"步长: {step}")
+    x, y = DrawGraph(a, b, step)