How to a turn a list of strings into complex numbers in python?

Question

I'm trying to write code which imports and exports lists of complex numbers in Python. So far I'm attempting this using the csv module. I've exported the data to a file using:

spamWriter = csv.writer(open('data.csv', 'wb')
spamWriter.writerow(complex_data)

Where complex data is a list numbers generated by the complex(re,im) function. Ex:

print complex_data
[(37470-880j),(35093-791j),(33920-981j),(28579-789j),(48002-574j),(46607-2317j),(42353-1557j),(45166-2520j),(45594-232j),(41149+561j)]

To then import this at a later time, I try the following:

mycsv = csv.reader(open('data.csv', 'rb'))
out = list(mycsv)
print out
[['(37470-880j)','(35093-791j)','(33920-981j)','(28579-789j)','(48002-574j)','(46607-2317j)','(42353-1557j)','(45166-2520j)','(45594-232j)','(41149+561j)']]

(Note that this is a list of lists, I just happened to use only one row for the example.)

I now need to turn this into complex numbers rather than strings. I think there should be a way to do this with mapping as in this question, but I couldn't figure out how to make it work. Any help would be appreciated!

Alternatively, if there's any easier way to import/export complex-valued data that I don't know of, I'd be happy to try something else entirely.

Answer 1

Just pass the string to complex():

>>> complex('(37470-880j)')
(37470-880j)

Like int() it takes a string representation of a complex number and parses that. You can use map() to do so for a list:

map(complex, row)

Answer 2

>>> c = ['(37470-880j)','(35093-791j)','(33920-981j)']
>>> map(complex, c)
[(37470-880j), (35093-791j), (33920-981j)]