how to make a nested list to a matrix without using numpy and bracket-CodePudding

a=[10*['-']]*10
print(a)
[['-', '-', '-', '-', '-', '-', '-', '-', '-', '-'], ['-', '-', '-', '-', '-', '-', '-', '-', '-', '-'],..]

how to make the "a" into a matrix without bracket and, finally turn something like this:

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I want to use the join function!!

CodePudding user response：

You can use two calls to .join() -- one to handle space separating the dashes, and one to handle printing the grid out on multiple lines:

print('\n'.join(' '.join('-' * 10) for _ in range(10)))

This outputs:

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