Stuff

mas/newton-raphsons/main.py

@@ -0,0 +1,34 @@
+#!/usr/bin/python
+import numpy as np
+
+def nullfunc(x):
+    return 0
+
+def derive(x: float, func=nullfunc, dx=0.1):
+    return (func(x+dx) - func(x))/dx
+
+def new_rap(x, func=nullfunc, dx=0.1):
+    new_x = None 
+    try:
+        while x != new_x:
+            y = func(x)
+            der = derive(x, func, dx)
+            new_x = x - y/der
+            if new_x == x:
+                return new_x 
+            else:
+                x = new_x
+        return x
+    except ZeroDivisionError as error:
+        print(f"{y=} {der=} {new_x=}")
+        print(error)
+
+
+def myfunc(x):
+    return 2*x - 2*(x**2) * np.sin(x) + 0.1
+
+
+if __name__ == "__main__":
+    out = new_rap(3, myfunc, 0.00000001)
+    print(f"x={out}")
+    print(f"f(x)={myfunc(out)}")

mas/newton-raphsons/sak.py

@@ -0,0 +1,57 @@
+#!/usr/bin/python
+import operator
+
+def new_rap(x, func: str="0", der: str="0", iter=0):
+    y_exper = func.replace("x", str(x)) 
+    der_exper = der.replace("x", str(x))
+
+    y = eval(y_exper)
+    der = eval(der_exper)
+
+    print(f"new_x = {x} - {y}/{der} [{iter}]")
+    new_x = x - (y / der)
+    return new_x
+
+# def new_rap(x, func=nullfunc, dx=0.1):
+#     new_x = None 
+#     try:
+#         while x != new_x:
+#             y = func(x)
+#             der = derive(x, func, dx)
+#             new_x = x - y/der
+#             if new_x == x:
+#                 return new_x 
+#             else:
+#                 x = new_x
+#         return x
+#     except ZeroDivisionError as error:
+#         print(f"{y=} {der=} {new_x=}")
+#         print(error)
+
+def eval_func( func: str, x: float ):
+    y_exper = func.replace("x", str(x)) 
+    return eval(y_exper)
+
+def new_rap_method(x, funcstr: str="0", derstr: str="0", per=10):
+    new_x = None
+    i = 0
+    while True:
+        y = eval_func(funcstr, x)
+        der = eval_func(derstr, x)
+
+        print(f"new_x = {x} - {y}/{der} [{i}]")
+        new_x = x - (y / der)
+        i += 1
+
+        if round(eval_func(funcstr, new_x), per) == 0:
+            return round(new_x, per)
+        else:
+            x = new_x
+
+if __name__ == "__main__":
+    func = input("f(x) = ")
+    der = input("f'(x) = ")
+    randx = float(input("x = "))
+    print("Doing newton-raphsons method to get root...")
+    x = new_rap_method(randx, func, der)
+    print(f"{x=}")