Python PCEP Multidemensional Arrays

1. Module 2
Data Collections – Lists, Tuples,
and Dictionaries
Multidimensional arrays

2. Module 2 Multidimensional arrays
Lists in lists
row = []
for i in range(8):
row.append(WHITE_PAWN)
row = [WHITE_PAWN for i in range(8)]
squares = [x ** 2 for x in range(10)]
#output [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
twos = [2 ** i for i in range(8)]
#output [1, 2, 4, 8, 16, 32, 64, 128]
squares = [x ** 2 for x in range(10)]
odds = [x for x in squares if x % 2 != 0 ]
print(odds)
#output [1, 9, 25, 49, 81]

3. Module 2 Multidimensional arrays
Two-dimensional arrays
board = []
for i in range(8):
row = [EMPTY for i in range(8)]
board.append(row)
EMPTY = "-"
ROOK = "ROOK"
board = []
for i in range(8):
row = [EMPTY for i in range(8)]
board.append(row)
board[0][0] = ROOK
board[0][7] = ROOK
board[7][0] = ROOK
board[7][7] = ROOK
print(board)
board = [[EMPTY for i in range(8)] for j in range(8)]

4. Module 2 Multidimensional arrays
Multidimensional nature of lists
two
coordinates
a vertical one
(row number)
a horizontal
one (column
number)
temps = [[0.0 for h in range(24)] for d in range(31)]
# The matrix is magically updated here.
total = 0.0
for day in temps:
total += day[11]
average = total / 31
print("Average temperature at noon:", average)
The monthly average noon temperature

5. Module 2 Multidimensional arrays
Multidimensional nature of lists
temps = [[0.0 for h in range(24)] for d in range(31)]
# The matrix is magically updated here.
highest = -100.0
for day in temps:
for temp in day:
if temp > highest:
highest = temp
print("The highest temperature was:", highest)
The highest temperature

6. Module 2 Multidimensional arrays
Multidimensional nature of lists
temps = [[0.0 for h in range(24)] for d in range(31)]
# The matrix is magically updated here.
hot_days = 0
for day in temps:
if day[11] > 20.0:
hot_days += 1
print(hot_days, "days were hot.")
The days when the temperature at noon was at least 20 ℃

7. Module 2 Multidimensional arrays
Three-dimensional arrays
• three buildings
• 15 floors each
• 20 rooms on each floor
the type of the array's elements(True/False)
calm analysis of the situation
rooms = [[[False for r in range(20)] for f in
range(15)] for t in range(3)]
In the second building,
on the tenth floor, room
14:
rooms[1][9][13] = True

8. Module 2 Multidimensional arrays
Key takeaways 1
[expression for element in list if conditional]
# A four-column/four-row table - a two
dimensional array (4x4)
table = [[":(", ":)", ":(", ":)"],
[":)", ":(", ":)", ":)"],
[":(", ":)", ":)", ":("],
[":)", ":)", ":)", ":("]]
print(table)
print(table[0][0]) # outputs: ':('
print(table[0][3]) # outputs: ':)'
list comprehension
use nested lists to
create matrices

9. Module 2 Multidimensional arrays
Key takeaways 2
# Cube - a three-dimensional array (3x3x3)
cube = [[[':(', 'x', 'x'],
[':)', 'x', 'x'],
[':(', 'x', 'x']],
[[':)', 'x', 'x'],
[':(', 'x', 'x'],
[':)', 'x', 'x']],
[[':(', 'x', 'x'],
[':)', 'x', 'x'],
[':)', 'x', 'x']]]
print(cube)
print(cube[0][0][0]) # outputs: ':('
print(cube[2][2][0]) # outputs: ':)'
create n-dimensional
lists

10. Congratulations!
You have completed Module 2
Well done! You've reached the end of Module 2
and completed a major milestone in your Python
programming education.