How to compare the elements of a nested list? - python-3.x

Question

I have some kind of matrix:
[[1,2,3],[1,2,3],[0,2,1],[1,2,3]] and I would like to be able to determine how many times I have the sequence 1,2,3 diagonally, vertically and horizontally but I have problems of index out of range for the last two loops. Thank you in advance for your answers!!
lista = [[1,2,3],[1,2,3],[0,2,1],[1,2,3]]
compteur_horizontal = 0
for i in range(len(lista)):
for c in range(len(lista[i])-2):
if lista[i][c] == 1 and lista[i][c+1] == 2 and lista[i][c+2] == 3:
compteur_horizontal += 1
print("ok")
compteur_vertical = 0
for c in range(len(lista)):
for j in range(len(lista[c])):
print(lista[j][c])
compteur_diagonale = 0
for j in range(len(lista)):
print(lista[i][i])
For the first counter, I would like it to be 3 since we have 3 times the sequence 1,2,3 horizontally. For the second counter, I would like it to be 0 because vertically there is no 1,2,3 sequence. And I'm waiting for a counter with 0 also since there's no 1,2,3 sequence in diagonal

Answer 1

Your code will not work even if you correct the current error. You need to change j and c in the second loop to resolve the error.
For horizontal and vertical here's the code. I'll add how to count diagonal ones later.
#lista = [[1, 2, 3],[1, 2, 3],[0, 2, 1],[1, 2, 3]]
lista = [[1,2,2],
[1,2,4],
[4,2,3],
[5,6,3]]
ptrn = [1, 2, 3]
# returns True is lst (1d array) has ptrn (1d array).
# e.g. lst[1,2,4,6,1,2,3,7], ptrn=[1,2,3] return True
# e.g. lst[1,2,4,6,1,4,3,7], ptrn=[1,2,3] return False
def is_pattern_in_a_list(lst, ptrn):
if ptrn[0] in lst:
idx = lst.index(ptrn[0])
for i in range(1, len(ptrn)):
if idx + i < len(lst):
if ptrn[i] != lst[idx+i]:
return False
else:
return False
return True
else:
return False
# counting horizontal occurances
count_h = 0
for row in lista:
if is_pattern_in_a_list(row, ptrn):
count_h += 1
# counting vertical occurances
# we first transpose the 2d array and use the same
# method of counting horizontal occurances.
def transpose_2d_array(a):
return [[a[j][i] for j in range(len(a))] for i in range(len(a[0]))]
lista_transpose = transpose_2d_array(lista)
count_v = 0
for row in lista_transpose:
if is_pattern_in_a_list(row, ptrn):
count_v += 1
# for diagonal occurances first we need to extract the diagonals
# with len >= len(ptrn).
# diagonals for the upper right triangle of the matrix:
count_d = 0
for i in range(len(lista[0])):
diag = []
j = 0
k = i
while j < len(lista)-i and k < len(lista[0]):
diag.append(lista[j][k])
j += 1
k += 1
if is_pattern_in_a_list(diag, ptrn):
count_d += 1
# diagonals for the lower left triangle of the matrix
i = len(lista) - 1
while i >= 1:
j = i
k = 0
diag = []
while j < len(lista) and k <= len(lista)+1-i:
diag.append(lista[j][k])
j += 1
k += 1
i -= 1
if is_pattern_in_a_list(diag, ptrn):
count_d += 1
print(diag)
print("Horizontal %d" % count_h)
print("Vertical %d" % count_v)
print("Diagonal %d" % count_d)