How do I print out a list as a matrix?

Question

Sorry for the noob-level question, but I'm trying to take a list of 10 names and put them into a 3x4 matrix, but I'm unsure how to do this when the input of the values was made by a loop. So instead of going `student0 = raw_input("Enter student 1's name: ")` ten times I have ``` students = [] for num in range(1, 11): students.append({ "name": raw_input("Enter Student %i's name: " % num), "absences": raw_input("Enter Student %i's absences: " % num) }) ``` but with the second (and more preferred) form, I don't know how to make the matrix. Before I could just type something like: ``` print("

Student Seating: 
") matrix = [[student0 + '		', student1 + '		', student2 + '		'], [student3 + '		', student4 + '		', student5 + '		'], [student6 + '		', 'Empty' + '		', student7 + '		'], ['Empty' + '		', student8 + '		', student9 + '		']] for row in matrix: print ' '.join(row) ``` But now (obviously) that doesn't work.. How would I fix this so I can take my list and put…

Accepted Answer

You could do this to partition groups of students into sub lists.

```
>>> students = [1,2,3,4,5,6,7,8,9,10] # assume numbers are students
>>> matrix = [ students[i:i+4] for i in range(0,len(students),4) ]
>>> for l in matrix:
...     print l
... 
[1, 2, 3, 4]
[5, 6, 7, 8]
[9, 10]
```

This has the advantage that no matter what the size of your `students` list, `matrix` will always have a max width 4.

How do I print out a list as a matrix?

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