From 3a52f4f220c9aecc30f59cc412cbc710d24c0e70 Mon Sep 17 00:00:00 2001
From: schrom01 <schrom01@students.zhaw.ch>
Date: Thu, 10 Nov 2022 20:57:49 +0100
Subject: [PATCH] implemented Gauss Algorythmus

---
 Schenk_Brandenberger_S6_Aufg2.py | 75 ++++++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)

diff --git a/Schenk_Brandenberger_S6_Aufg2.py b/Schenk_Brandenberger_S6_Aufg2.py
index e69de29..7b03434 100644
--- a/Schenk_Brandenberger_S6_Aufg2.py
+++ b/Schenk_Brandenberger_S6_Aufg2.py
@@ -0,0 +1,75 @@
+import numpy as np
+
+
+def switchRows(matrix, row1, row2):
+    matrix[[row1, row2]] = matrix[[row2, row1]]
+    return matrix
+
+
+
+def gaussAltorithmus(A, b):
+
+    def calculateRow(A, b, row, column):
+        b[row] = [b[row][0] - (A[row][column] / A[column][column]) * b[column][0]]
+        A[row] = [(A[row][i] - (A[row][column] / A[column][column]) * A[column][i]) for i in range(len(A[row]))]
+        return A, b
+
+    # Erstelle obere Dreiecksmatrix
+    columnsToEdit = []
+    for row in range(1, len(A)):
+        columnsToEdit.append(row - 1)
+        for column in columnsToEdit:
+            print("Zeile", row, "Spalte", column)
+            if(A[row-1][column] == 0 and (row - 1 == column)):
+                rowToSwitch = row
+                if(row == 1):
+                    while(A[rowToSwitch][column] == 0):
+                        if(len(A) > rowToSwitch + 1):
+                            rowToSwitch += 1
+                        else:
+                            return "Matrix ist nicht regulär!"
+                A = switchRows(A, row - 1, rowToSwitch)
+                b = switchRows(b, row - 1, rowToSwitch)
+            else:
+                A, b = calculateRow(A, b, row, column)
+
+            print("\nA\n", A, "\nb\n", b)
+
+    # Rückwärtseinsetzen
+    columnsToEdit = []
+    for row in range((len(A) - 2), -1, -1):
+        columnsToEdit.append(row + 1)
+        for column in columnsToEdit:
+            A, b = calculateRow(A, b, row, column)
+            print(A)
+            print(b)
+        row -= 1
+        print("\nA\n", A, "\nb\n", b)
+
+    result = []
+    for i in range(len(A)):
+        result.append(b[i][0] / A[i][i])
+    return result
+
+
+
+if __name__ == '__main__':
+    # Beispiel aus Vorlesungsfolen:
+    A = np.array([[1.0, 5.0, 6.0],
+                  [7.0, 9.0, 6.0],
+                  [2.0, 3.0, 4.0]])
+    b = np.array([[29.0],
+                   [43.0],
+                   [20.0]])
+
+    # A = np.array([[1.0, 1.5, 2.0],
+    #                [2.0, 3.0, 5.0],
+    #                [0.0, 1.0, 2.0]])
+    #
+    # b = np.array([[16.0],
+    #                [35.0],
+    #                [12.0]])
+
+    result = gaussAltorithmus(A, b)
+    for i in range(len(result)):
+        print("x" + str(i) + ": " + str(result[i]))
\ No newline at end of file