Question

我是Python的新手，我需要制作代码，计算每个数字出现在与特定键相关联的列表中的次数。然后程序应该在单独的行上打印出这些计数

我能够打印掉计数，但是我无法在不同的行上打印它们。以下是我迄今为止所做的事情：

import json

#####

def read_json(filename):
    dt = {}

    fh = open(filename, "r")
    dt = json.load(fh)

    return dt

##### 

def num_counter(dt):

    numbers = dt["daily_stock_prices"]


    counter = {}

    for number in numbers:
        counter[number] = 0

    for number in numbers:
         counter[number] += 1

    print counter

#####

filename = raw_input('Please enter the file name: ')

#####

r = read_json(filename)
num_counter(r)

我试图在单独的线上打印计数器，如下所示，但我仍然没有成功。有什么建议？我也不确定在我的代码中包含它的位置。

def print_per_line(number_counts):

    for number in number_counts.key():

            count = word_counts[word]       

            print word,count

如果需要，这是列表：

{
    "ticker": "MSFT",
    "daily_stock_prices": [0,1,5,10,12,15,11,9,9,5,15,20]
}

最终输出应为：

item: count
item: count
...

Answer 1

试试这个：

def num_counter(dt):
    numbers = dt["daily_stock_prices"]
    counter = {}
    for number in numbers:
        counter[number]= counter.get(number, 0) + 1
    return counter

def print_per_line(num_count):
    for k,v in counter.iteritems():
       print str(k) + ":  " + str(v)

# You call them like this
r = read_json(filename)
num_count = num_counter(r)
print_per_line(num_count)

Answer 2

以下是使用和不使用collections模块的方法。

import collections
import json

# Here is the sample data
data = """{
    "ticker": "MSFT",
    "daily_stock_prices": [0,1,5,10,12,15,11,9,9,5,15,20]
}"""

# It's easiest to parses it with as JSON.
d = json.loads(data)

# You can use the collections module to count.
counts = collections.Counter(d['daily_stock_prices'])

# Or you can create a dictionary of the prices.
pricedict = {}
for price in d['daily_stock_prices']:
    if pricedict.has_key(price):
        pricedict[price] += 1
    else:
        pricedict[price] = 1

# Print output - you could substitute counts for pricedict. 
for k,v in pricedict.iteritems():
    print("{} - {}".format(k, v))

输出

计算列表中每个数字的外观并将它们打印在单独的行上

2 个答案: