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![Shane Singh](https://uploads.teamtreehouse.com/production/profile-photos/2512182/micro_Sample.jpg)
Shane Singh
5,440 PointsTransposing my array?
I am a novice programmer in python and was wondering if I can get a little help. The code I am about to show below prints out a simple array based on the users input for # of rows and # of columns.
new_list = []
undersc = '_'
for i in range(1, rows + 1):
new = []
for j in range(1, columns + 1)
new.append(undersc if j > i else 'Z')
new_list.append(new)
for c in range(len(new_list[0])):
print()
for r in range(len(new_list)):
for c in range(len(new_list[0]))
array = print((new_list[r][c]), end=" ")
print()
return array
The console outputs the following:
Z _ _ _ _
Z Z _ _ _
Z Z Z _ _
I am completely lost as to how I would transpose my array in other words swap the columns with the rows. Any help would be greatly appreciated!
1 Answer
![Chris Freeman](https://uploads.teamtreehouse.com/production/profile-photos/1153532/micro_image.jpg)
Chris Freeman
Treehouse Moderator 68,425 PointsYou have all the information you need. To reverse the columns and rows exchange your inner and outer loops:
# initial print loop
for r in range(len(new_list)):
for c in range(len(new_list[0])):
array = print((new_list[r][c]), end=" ")
print()
# transposed print loops
for c in range(columns):
for r in range(rows):
array = print((new_list[r][c]), end=" ")
print()
Compressing and cleaning up your code a bit:
def array2(rows, columns):
new_list = []
undersc = '_'
# i and j are relative counters, no need to use 1-based counting
for i in range(rows):
new = []
for j in range(columns):
new.append(undersc if j > i else 'Z')
new_list.append(new)
# this prints out many blank lines. Not clear why it's needed
# for c in range(len(new_list[0])):
# print()
for c in range(columns):
for r in range(rows):
# print does not return object, assignment to 'array' not needed
print((new_list[r][c]), end=" ")
print()
# no value being returned, explicit 'return' not needed
# return array
Produces:
>>> array2(3, 4)
Z Z Z
_ Z Z
_ _ Z
_ _ _