Hw1

my_homework1.py

@@ -0,0 +1,116 @@
+from array import array
+class Iterator: #additional class for __iter__()
+    def __init__(self, collection):
+        self.cursor = -1
+        self._collection = collection
+    def __next__(self,default=None):
+        if self.cursor + 1 >= len(self._collection):
+            self.cursor = -1
+            raise StopIteration
+        self.cursor +=1
+        return self._collection[self.cursor]
+
+types_dict = {int: 'i', str: 'u', float: 'd'} #matching dict
+class ArrayList:
+    def __init__(self,datatype,initializer=()):
+        typecode = types_dict[datatype]
+        for x in initializer:
+            if type(x) != datatype:
+                raise Exception("Wrong initializer datatype") #fixed
+        self._arr = array(typecode, initializer)
+        self._iterator = Iterator(self._arr)
+
+    def __getitem__(self, key): #fixed (slice added) - working only for int type
+        cls = type(self)
+        if isinstance(key,slice):
+            return cls(int,self._arr[key])
+        elif isinstance(key,int):
+            return self._arr[key]
+        else:
+            raise IndexError
+
+    def __repr__(self):
+        return f"{self._arr}"
+
+    def __len__(self):
+        return self._arr.buffer_info()[1] # buffer_info return a tuple (address, length)
+
+    def __contains__(self, elem):
+        for x in range(self.__len__()): #fixed
+            if self._arr[x] == elem:
+                return True
+
+    def __iter__(self):
+        return self._iterator
+        # for i in range(self._arr.buffer_info()[1]):
+        #     yield self._arr[i]
+
+    def __reversed__(self):
+        return self._arr[::-1]
+
+    def __index__(self,item):
+        for i, x in enumerate(self._arr):
+            if x == item:
+                return i
+
+    def __count__(self, item):
+        c = 0
+        for x in self._arr:
+            if x == item:
+                c += 1
+        return c
+
+
+
+#int
+print('int tests: ')
+print()
+a = ArrayList(int, (1,4,5,4,3,5,64,43,6))
+
+print('slice test: ', a[0:3])
+print('getitem test: ', a.__getitem__(3))
+print('len test: ', a.__len__())
+print('contains test: ', a.__contains__(64))
+print('iter test: ')
+for k in a:
+    print(k, end=' ')
+print()
+print('reversed test: ')
+print(a.__reversed__())
+print('index test: ',a.__index__(64))
+print('count test: ',a.__count__(4))
+
+#str
+print('str tests: ')
+print()
+a1 = ArrayList(str, ('x','y','z','x','z','p','q'))
+
+print('getitem test: ', a1.__getitem__(3))
+print('len test: ', a1.__len__())
+print('contains test: ', a1.__contains__('x'))
+print('iter test: ')
+for k in a1:
+    print(k, end=' ')
+print()
+print('reversed test: ')
+print(a1.__reversed__())
+print('index test: ',a1.__index__('q'))
+print('count test: ',a1.__count__('x'))
+
+#float
+print('float tests: ')
+print()
+a2 = ArrayList(float, (1.1,1.2,1.3,1.4,1.4,1.5,1.2,1.7))
+
+print('getitem test: ', a2.__getitem__(3))
+print('len test: ', a2.__len__())
+print('contains test: ', a2.__contains__(1.7))
+print('iter test: ')
+for k in a2:
+    print(k, end=' ')
+print()
+print()
+print('reversed test: ')
+print(a2.__reversed__())
+print('index test: ',a2.__index__(1.1))
+print('count test: ',a2.__count__(1.4))