ValueError：太多的值解包（预期2）

Question

I'm trying to parse DNA strings.

The input.txt contains:

Rosalind_6404CCTGCGGAAGATCGGCACTAGAATAGCCAGAACCGTTTCTCTGAGGCTTCCGGCCTTCCCTCCCACTAATAATTCTGAGG>Rosalind_5959CCATCGGTAGCGCATCCTTAGTCCAATTAAGTCCCTATCCAGGCGCTCCGCCGAAGGTCTATATCCATTTGTCAGCAGACACGC>Rosalind_0808CCACCCTCGTGGTATGGCTAGGCATTCAGGAACCGGAGAACGCTTCAGACCAGCCCGGACTGGGAACCTGCGGGCAGTAGGTGGAAT

The code is:

f = open('input.txt', 'r')
raw_samples = f.readlines()
f.close()
samples = {}
cur_key = ''
for elem in raw_samples:
    if elem[0] == '>':
        cur_key = elem[1:].rstrip()
        samples[cur_key] = ''
    else:
        samples[cur_key] = samples[cur_key] + elem.rstrip()
print(samples)
for p_id, s in samples.values():
    samples[s_id] = (s.count('G') + s.count('C'))*100
print (samples)`

I keep getting the error:

  File "C:/Python34/test.py", line 18, in <module> for p_id, s in samples.values(): ValueError: too many values to unpack (expected 2) 

Answer 1

I was able to solve the problem by changing for p_id, s in samples.values() to for p_id, s in samples.items()

I also noticed that p_id and s_id were different, they were meant to be the same.

Answer 2

import csv
reader = csv.reader(open("input.txt"), delimiter=">", quotechar="'")
dkeys = [item for item in next(reader) if item.strip()]
dvalues = [(item.count('G')+item.count('C')*100) for item in dkeys]
print(dict(zip(dkeys, dvalues)))

I hope it's useful. :D