python 3.5.0 :::: MAGIC SQUARE

Question

I'm trying to built a magic square:

A magic square is one divided in rows and columns, with a number in each position and which the sum of rows, columns and diagonals is the same. Example (3x3 - numbers from 1 to 9):

8 3 4

1 5 9

6 7 2

I tried to use a matrix 3x3 and a vector with 9 indexes.

import random
                #j(column)
matriz = [[1, 2, 3],#i(row)
          [4, 5, 6],
          [7, 8, 9]]
res = False
#DEFINE A FUNCTION TO CALCULATE ALL SUMS OF ALL SIDES
def magicsquare():
    if matriz[0][0] + matriz[1][0] + matriz[2][0] == matriz[0][1] + matriz[1][1] + matriz[2][1] == matriz[0][2] + matriz[1][2] + matriz[2][2] == matriz[0][0] + matriz[0][1] + matriz[0][2] == matriz[1][0] + matriz[1][1] + matriz[1][2] == matriz[2][0] + matriz[2][1] + matriz[2][2] == matriz[0][0] + matriz[1][1] + matriz[2][2] == matriz[0][2] + matriz[1][1] + matriz[2][0]:
        return res = True
    else:
        return res = False

#DEFINE A LOOP TO GENERATE RANDOM NUMBER UNTIL FIND THE ONES THAT
#SATISFY THE CONDITIONS OF A MAGIC SQUARE
seq = [1, 2, 3, 4, 5, 6, 7, 8, 9]
while res == False:
    for i in range(2):
        for j in range(2):
            z = random.choice(seq)
            matriz[i][j] = z
            x = seq.index(z)
            seq[x] = []
    magicsquare()
print (matriz)
#---------------------------------------------------------------------------------------------------------------------------------------------------------------
res = False
def magicsquare():
    if vetor[0] + vetor[1] + vetor[2] == vetor[3] + vetor[4] + vetor[5] == vetor[6] + vetor[7] + vetor[8] == vetor[0] + vetor[3] + vetor[6] == vetor[1] + vetor[4] + vetor[7] == vetor[2] + vetor[5] + vetor[8] == vetor[0] + vetor[4] + vetor[8] == vetor[2] + vetor[4] + vetor[6]:
        return res == True
    else:
        return res == False
#        0  1  2  3  4  5  6  7  8
vetor = [1, 2, 3, 4, 5, 6, 7, 8, 9]
seq =   [1, 2, 3, 4, 5, 6, 7, 8, 9]
if res == False:
    for i in range(8):
        w = random.choice(seq)
        #Replace the value w in index i
        vetor.insert(i, w)
        #Eliminate the valyes already used
        x = seq.index(w)
        seq[x] =[]
    magicsquare()
print (vetor)

The result is always: [1, 2, 3, 4, 5, 6, 7, 8, 9]

Can anyone help me built a magic square and tell what's wrong with my code?

Using Python 3.5.0

is it helpful? http://pydoc.net/Python/magic_square/0.2/magic_square/ — Paweł Kordowski, Nov 22 '15 at 13:14
also have a look: http://stackoverflow.com/questions/104420/how-to-generate-all-permutations-of-a-list-in-python — Emile Vrijdags, Nov 22 '15 at 13:28

xmcp · Accepted Answer · 2015-11-22T13:27:00.663

Your randomizing code is wrong.

>>> 
Traceback (most recent call last):
  File "C:/Users/xiao/Desktop/ms.py", line 20, in <module>
    magicsquare()
  File "C:/Users/xiao/Desktop/ms.py", line 5, in magicsquare
    if vetor[0] + vetor[1] + vetor[2] == vetor[3] + vetor[4] + vetor[5] == vetor[6] + vetor[7] + vetor[8] == vetor[0] + vetor[3] + vetor[6] == vetor[1] + vetor[4] + vetor[7] == vetor[2] + vetor[5] + vetor[8] == vetor[0] + vetor[4] + vetor[8] == vetor[2] + vetor[4] + vetor[6]:
TypeError: unsupported operand type(s) for +: 'int' and 'list'
>>> vetor
[9, 4, 8, 2, 3, [], [], [], 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>>

random module has a method called shuffle for shuffling a list. If you have no idea about your code, just use random.shuffle.

Plus, there are 2 ways to stop the while loop. The first way is to change the global variable res in function magicsquare:

def magicsquare():
    global res
    if ...:
        res = True
    else:
        res = False

The other way is to return the condition in magicsquare:

import random

vetor = [1, 2, 3, 4, 5, 6, 7, 8, 9]

def magicsquare():
    return vetor[0]+vetor[1]+vetor[2]==\
           vetor[3]+vetor[4]+vetor[5]==\
           vetor[6]+vetor[7]+vetor[8]==\
           vetor[0]+vetor[3]+vetor[6]==\
           vetor[1]+vetor[4]+vetor[7]==\
           vetor[2]+vetor[5]+vetor[8]==\
           vetor[0]+vetor[4]+vetor[8]==\
           vetor[2]+vetor[4]+vetor[6]

while not magicsquare():
    random.shuffle(vetor)

print (vetor)

score 0 · Answer 2 · answered Dec 07 '22 at 14:46

    def forEvenNumber(n):
    arr = [[(n * y) + x + 1 for x in range(n)] for y in range(n)]
    for i in range(0, n // 4):
        for j in range(0, n // 4):
            arr[i][j] = (n * n + 1) - arr[i][j];
    for i in range(0, n // 4):
        for j in range(3 * (n // 4), n):
            arr[i][j] = (n * n + 1) - arr[i][j];
    for i in range(3 * (n // 4), n):
        for j in range(0, n // 4):
            arr[i][j] = (n * n + 1) - arr[i][j];
    for i in range(3 * (n // 4), n):
        for j in range(3 * (n // 4), n):
            arr[i][j] = (n * n + 1) - arr[i][j];
    for i in range(n // 4, 3 * (n // 4)):
        for j in range(n // 4, 3 * (n // 4)):
            arr[i][j] = (n * n + 1) - arr[i][j];
    print("\nSum of all row, column and diagonals = ",
          n * (n * n + 1) // 2, "\n")
    for i in range(n):
        for j in range(n):
            print('%2d ' % (arr[i][j]), end=" ")
        print()
def forOddNumber(n):
    mgsqr = [[0 for x in range(n)]
             for y in range(n)]
    r = n // 2
    c = n - 1
    num = 1
    while num <= (n * n):
        if r == -1 and c == n:
            c = n - 2
            r = 0
        else:
            if c == n:
                c = 0
            if r < 0:
                r = n - 1
        if mgsqr[int(r)][int(c)]:
            c = c - 2
            r = r + 1
            continue
        else:
            mgsqr[int(r)][int(c)] = num
            num = num + 1
        c = c + 1
        r = r - 1
    print("\nSum of all row, column and diagonals = ",
          n * (n * n + 1) // 2, "\n")
    for i in range(0, n):
        for j in range(0, n):
            print('%2d ' % (mgsqr[i][j]), end='')
        print()
print("\nWELCOME:)\n")
n = int(input("Please Enter Number of Rows and Column (n*n): "))
if n%2==0:
    forEvenNumber(n)
else:
    forOddNumber(n)
print("\nThank You :)")

score -1 · Answer 3 · answered Jul 07 '21 at 18:50

try my code..

box = []

num = [1, 2, 3,
       4, 5, 6,
       7, 8, 9]

val = []

for i in num:
    for j in num:
        for k in num:
            if ((i+j+k) == 15) and i != j and j != k and k != i:
                val.append((i, j, k))


def check_sum(lst: list):
    rtn = []
    res = 0
    lst = lst[0]
    for c in range(3):
        for r in range(3):
            res += lst[r][c]
        if res == 15:
            rtn.append(True)

        else:
            rtn.append(False)

        res = 0

    res = 0

    for x in range(3):
        for y in range(3):
            if x == y:
                res += lst[x][y]

    if res == 15:
        rtn.append(True)

    else:
        rtn.append(False)

    res = 0

    for x in range(3):
        for y in range(3):
            if x+y == 2:
                res += lst[x][y]

    if res == 15:
        rtn.append(True)

    else:
        rtn.append(False)

    return all(rtn)


def is_unique(a, b, c):
    st = set()
    for x in a:
        st.add(x)

    for x in b:
        st.add(x)

    for x in c:
        st.add(x)

    if len(st) == 9:
        return True
    else:
        return False


def print_box(b):
    for row in b[0]:
        print(row)
    print()


for i in val:
    for j in val:
        for k in val:
            if is_unique(i, j, k):
                box.append([i, j, k])
                if check_sum(box):
                    print_box(box)
                if len(box) == 1:
                    box.clear()

output is:

(2, 7, 6)
(9, 5, 1)
(4, 3, 8)

(2, 9, 4)
(7, 5, 3)
(6, 1, 8)

(4, 3, 8)
(9, 5, 1)
(2, 7, 6)

(4, 9, 2)
(3, 5, 7)
(8, 1, 6)

(6, 1, 8)
(7, 5, 3)
(2, 9, 4)

(6, 7, 2)
(1, 5, 9)
(8, 3, 4)

(8, 1, 6)
(3, 5, 7)
(4, 9, 2)

(8, 3, 4)
(1, 5, 9)
(6, 7, 2)

python 3.5.0 :::: MAGIC SQUARE

Can anyone help me built a magic square and tell what's wrong with my code?

3 Answers3