如何读取文件并将它们存储在字典中。 不使用 zip

Question

I need to read the file that contains first line as a key and the second line as a value. I am able to open the file and read it but i am not able to assign it to the dictionary format.

def ticker(n):
infile = open(n)
content = infile.readlines()
c = {}
for lines in content:
    print (lines)

Below is my output, but i am not able to assign the first line to key and second line to value.

WHOLE FOODS MARKET
WFMI
WYNN RESORTS, LTD
WYNN
XILINX
XLNX
XM SATELLITE RADIO HOLDINGS
XMSR
YAHOO
YHO

Thanks.

Answer 1

Use a dict generator:

{content[i]:content[i+1] for i in range(0, len(content)-1, 2)}

In your code like so:

def ticker(n):
    infile = open(n)
    content = infile.readlines()
    infile.close()  # Remember to close your file objects... (or use with block)
    return {content[i].strip():content[i+1].strip() for i in range(0, len(content)-1, 2)}

Or, as @ShadowRanger suggests using zip and slices:

def ticker(n):
    with open(n) as infile:
        content = infile.readlines()
        return dict(zip(content[::2], content[1::2]))

Answer 2

You'd use zip , but not with tee , since that would pair all lines with their next line, not even lines with odd. To pair even with odd, do:

def ticker(file_name):
   with open(file_name) as f:
      stripped = iter(map(str.rstrip, f))
      return dict(zip(*([stripped] * 2)))

This is just wrapping a dict constructor around an inlined version of the grouper itertools recipe , though using zip since we know it's paired up.