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Transform "list of tuples" into a flat list or a matrix

Asked 2012-05-17T09:16:58.540
128

With Sqlite, a select .. from command returns the results output, which prints:

>>print output
[(12.2817, 12.2817), (0, 0), (8.52, 8.52)]

It seems to be a list of tuples. I would like to either convert output to a simple list:

[12.2817, 12.2817, 0, 0, 8.52, 8.52]

or a 2x3 matrix:

12.2817 12.2817
0          0 
8.52     8.52

to be read via output[i][j]

The flatten command does not do the job for the 1st option, and I have no idea for the second one...

A fast solution would be appreciated, as the real data is much bigger.

python list tuples
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2 Answers

7

Or you can flatten the list like this:

reduce(lambda x,y:x+y, map(list, output))
answered 2012-05-17T11:05:38.370
3

In case of arbitrary nested lists(just in case):

def flatten(lst):
    result = []
    for element in lst: 
        if hasattr(element, '__iter__'):
            result.extend(flatten(element))
        else:
            result.append(element)
    return result

>>> flatten(output)
[12.2817, 12.2817, 0, 0, 8.52, 8.52]
answered 2012-05-17T10:03:21.833

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