Question

I am using the following code to get frequency of letters in a text:

for s in 'abcdefghijklmnopqrstuvwxyz ':
    count = 0
    for char in rawpunct.lower():
        if s == char:
            count +=1
    result = s, '%.3f' % (count*100/len(rawpunct.lower()))
    f_list.append(result)

And the result is :

['0.061', '0.012', '0.017', '0.030', '0.093', '0.016', '0.016', 
'0.049', '0.050', '0.001', '0.006', '0.034', '0.018', '0.052', '0.055',
 '0.013', '0.001', '0.041', '0.050', '0.069', '0.021', '0.007', '0.017',
 '0.001', '0.013', '0.000', '0.159']

but I want to store the cumulative frequencies, i.e create this list :

['0.061', '0.073', '0.100', '0.130' ............ ]

Anyone know how to do this?

Answer 1

Just for the fun of the one-liner :

original = ['0.061', '0.012', '0.017', '0.030', '0.093', '0.016', '0.016', 
'0.049', '0.050', '0.001', '0.006', '0.034', '0.018', '0.052', '0.055',
 '0.013', '0.001', '0.041', '0.050', '0.069', '0.021', '0.007', '0.017',
 '0.001', '0.013', '0.000', '0.159']

result = [sum(float(item) for item in original[0:rank+1]) for rank in xrange(len(original))]

>>> [0.061, 0.073, 0.09, 0.12, 0.213, 0.22899999999999998, 0.245, 0.294, 0.344, 0.345, 0.351, 0.385, 0.403, 0.455, 0.51, 0.523, 0.524, 0.5650000000000001, 0.6150000000000001, 0.6840000000000002, 0.7050000000000002, 0.7120000000000002, 0.7290000000000002, 0.7300000000000002, 0.7430000000000002, 0.7430000000000002, 0.9020000000000002]