init()

.idea/.gitignore

@@ -0,0 +1,8 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml

s1_a4.py

@@ -1,9 +1,10 @@
 import math
 if __name__ == "__main__":
-    row_value = round(math.pi**2/6, 6)  # = 1.644934
-    sum_of_reciprocal_squares = 0
+    # 4.1
+    series_value = round(math.pi**2/6, 6)
+    approximate_value = 0
     divider = 1
-    while row_value != round(sum_of_reciprocal_squares, 6):
-        sum_of_reciprocal_squares += 1/divider**2
+    while series_value != round(approximate_value, 6):
+        approximate_value += 1/divider**2
         divider += 1
-    print("After adding the first " + str(divider-1) + " reciprocal square numbers the sum equals " + str(round(sum_of_reciprocal_squares, 6)))
+    print("The sum equals", series_value, "after adding", divider-1, "reciprocal square numbers.")

s1_a51.py

@@ -1,56 +1,24 @@
-import collections
-import numpy as np
-from scipy import sparse
-
-
-class Matrix:
+class SparseMatrix:
     def __init__(self):
-        self.__matrix = collections.defaultdict(dict)
+        self.__matrix = dict()
 
-    def set(self, row, column, value):
-        if value != 0:
-            self.__matrix[row][column] = value
-        else:
-            if self.__matrix.get(row) and self.__matrix.get(row).get(column):
-                del self.__matrix[row][column]
+    def save(self, matrix) -> None:
+        for row in range(len(matrix)):
+            for col in range(len(matrix[row])):
+                if matrix[row][col] != 0:
+                    self.__matrix[(row, col)] = matrix[row][col]
 
-    def get(self, row, column):
-        if self.__matrix.get(row) and self.__matrix.get(row).get(column):
-            return self.__matrix[row][column]
-        else:
-            return 0
+    def get(self, row, col) -> int or None:
+        if self.__matrix[(row, col)]:
+            return self.__matrix[(row, col)]
 
-    def print(self):
-        print(self.__matrix)
+    def __str__(self) -> str:
+        return '\n'.join(map(lambda pair: ': '.join(map(str, pair)), self.__matrix.items()))
 
 
 if __name__ == "__main__":
-    # Aufgabe 1b
-    input_matrix = [[3, 0, -2, 11],
-                    [0, 0, 9, 0],
-                    [0, 7, 0, 0],
-                    [0, 0, 0, 0]]
-
-    # sparse_matrix = Matrix()
-    #
-    # for row in range(len(input_matrix)):
-    #     for column in range(len(input_matrix[0])):
-    #         sparse_matrix.set(row, column, input_matrix[row][column])
-
-    sparce_matrix = {}
-    rows = len(input_matrix)
-    columns = len(input_matrix[0])
-
-    for row in range(rows):
-        for column in range(columns):
-            if input_matrix[row][column] != 0:
-                sparce_matrix[(row, column)] = input_matrix[row][column]
-
-    # Aufgabe 1c
-    print("\n The sparce matrix without numpy\n" + str(sparce_matrix))
-    # sparse_matrix.print()
-    # faster way with numpy
-    input_matrix = np.array(input_matrix)
-    rows, columns = input_matrix.shape
-    sparse_matrix = sparse.csr_matrix(input_matrix)
-    print("\nThe sparce matrix computed with numpy\n" + str(sparse_matrix))
+    # 5.1
+    sparse_matrix = SparseMatrix()
+    sparse_matrix.save([[3, 0, -2, 11], [0, 0, 9, 0], [0, 7, 0, 0], [0, 0, 0, 0]])
+    print(sparse_matrix)
+    print(sparse_matrix.get(0, 0))

s1_a53_6.py

@@ -1,38 +1,19 @@
 if __name__ == "__main__":
-    # Aufgabe 3
-    numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
-    numbers = numbers[-3:] + numbers[:-3]
-    print(numbers)
+    # 5.3
+    nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+    print(nums[-3:] + nums[:-3])
 
-    # Aufgabe 4
-    def split_chars_and_remove_duplicates(word: str):
-        string_list = list(word)
-        print("Length of the string-list with duplicates: " + str(len(string_list)))
-        string_set = set(string_list)
-        string_list = list(string_set)
-        string_list.sort()
-        print("Length of the string-list without duplicates: " + str(len(string_list)))
-        print(string_list)
+    # 5.4
+    def remove_duplicates(word: str):
+        result = "".join(sorted(set(word), key=word.index))
+        print(word, len(word), "\n", result, len(result))
+    remove_duplicates("Donaudampfschiffahrtsgesellschaftsstewardess")
 
+    # 5.5
+    nums = [[1, 2, 3], [2, 1, 3], [4, 0, 1]]
+    nums.sort(key=lambda x: x[1])
 
-    string = "Donaudampfschiffahrtsgesellschaftsstewardess"
-    split_chars_and_remove_duplicates(string)
-
-    # Aufgabe 5
-    list_to_sort = [[1, 2, 3], [2, 1, 3], [4, 0, 1]]
-    list_to_sort.sort(key=lambda x: x[1])  # in-build-function
-
-    for row in range(len(list_to_sort)):
-        for next_row in range(row + 1, len(list_to_sort)):
-            if list_to_sort[row][1] > list_to_sort[next_row][1]:
-                list_to_sort[row], list_to_sort[next_row] = list_to_sort[next_row], list_to_sort[row]
-
-    print("The sorted list " + str(list_to_sort))
-
-    # Aufgabe 6
-    def get_the_animal_sound(name_of_animal: str):
-        animal_dictionary = {"Lion": "Growl!", "Dog": "Barks!", "Cat": "Meow!"}
-        return animal_dictionary.get(name_of_animal, "Animal sound not available")
-
-
-    print(get_the_animal_sound("Dog"))
+    # 5.6
+    def get_animal_sound(animal: str) -> str:
+        animal_dictionary = {"Lion": "Growl", "Dog": "Bark", "Cat": "Meow"}
+        return animal_dictionary.get(animal, "Not found.")

s1_a61_2.py

@@ -1,10 +1,7 @@
 if __name__ == "__main__":
-    # Aufgabe 6.1
-    string_with_spaces = "This is a test"
-    string_with_dashes = string_with_spaces.replace(" ", "-")
-    print(string_with_dashes)
+    # 6.1
+    print("This is a test".replace(" ", "-"))
 
-    # Aufgabe 6.2
+    # 6.2
     s1 = "Hello, World"
-    s2 = s1[s1.find(","):0:-1]
-    print(s2)
+    print(s1[s1.find(",")::-1])