使用字典来计算字符串中的第一个字母 - Python

Question

我一直在Python中进行字典练习，而且我本身对语言和编程本身也很陌生。我一直在尝试使用一个字符串或字符串列表，并让我的代码比较字符串的第一个字母，并将多少个字符串以字母表中的某个字母开头的字典作为字典。这是我到目前为止有：

d = {} 
text=["time","after","time"] 
# count occurances of character 
for w in text: 

    d[w] = text.count(w) 
# print the result 
for k in sorted(d): 
    print (k + ': ' + str(d[k])) 

我的目标是什么，是例如得到以下结果：

count_starts(["time","after","time"]) -->{'t': 2, 'a': 1} 

但是，什么我越来越更像是以下几点：

count_starts(["time","after","time"]) --> {time:2, after:1} 

与我有什么，我已经能够完成它计数整个唯一的字符串出现了多少次，只是不只是字符串中的第一个字母的计数。

我也试过如下：

d = {} 
text=["time","after","time"] 
# count occurances of character 
for w in text: 
    for l in w[:1]: 
     d[l] = text.count(l) 
# print the result 
for k in sorted(d): 
    print (k + ': ' + str(d[k])) 

但所有的给我打印输出是：

{"a":0,"t":0} 

我使用Python展台为我的测试目的。

Answer 1

d = {} 

text = ['time', 'after', 'time'] 

for w in text: 
    if w:       # If we have the empty string. w[0] Does not Exist (DNE) 
     if w[0] in d:    # Check to see if we have first character in dictionary. 
      d[w[0]] = d[w[0]] + 1 # Use the first character as key to dictionary. 
     else:      # If character has not been found start counting. 
      d[w[0]] = 1   # Use the first character as key to dictionary. 

使用Python的IDLE我得到：

>>> d = {} 
>>> text = ['time', 'after', 'time'] 
>>> for w in text: 
    if w: 
     if w[0] in d: 
      d[w[0]] = d[w[0]] + 1 
     else: 
      d[w[0]] = 1 

>>> print d 
{'a': 1, 't': 2} 
>>> 

Answer 2

要计算的第一个字母的出现为每个项目的文本数量：

from collections import Counter 

text = ["time", "after", "time"] 

>>> Counter(t[0] for t in text) 
Counter({'a': 1, 't': 2}) 

或刚刚起步的字典键/值对：

>>> dict(Counter(t[0] for t in text)) 
{'a': 1, 't': 2}