Question

代码

library(dplyr)

df <- tibble(a = c(2, 3, 2, 1, 0),
                b = c(2, 3, 3, 2, 1),
                z = c(3, 2, 1, 1, 0))

df <- df %>%
      mutate(sum_values = case_when((a > 1 | b > 1) & (z > 0) ~ (a+b+z),
                                    TRUE ~ 0))

结果

fav_numbers = {
    'bill': [4,6,7,1],
    'uros': [9,0,1,2],
    'pera': [1,6,3,5],
    }

for name, numbers in fav_numbers.items():
    print(name.title())
    for num in numbers:
        print(num, end=' ')

问题如何编写for循环，以便最后两个名称正确格式化？

Answer 1

只需在循环末尾添加另一个print即可开始新行：

for name, numbers in fav_numbers.items():
    print(name.title())
    for num in numbers:
        print(num, end=' ')
    print()

在这里live

Answer 2

fav_numbers = {
    'bill': [4,6,7,1],
    'uros': [9,0,1,2],
    'pera': [1,6,3,5],
    }

for k,v in fav_numbers.items():
    print(k, *v)

输出

bill 4 6 7 1
uros 9 0 1 2
pera 1 6 3 5

Answer 3

问题不是end=' '，而是缺少它的print(name.title())。还要添加end= '，以便将数字打印到同一行中，然后以print()结尾作为最后的换行符。

for name, numbers in fav_numbers.items():
    print(name.title(), end=' ')  # no newline here
    for num in numbers:
        print(num, end=' ')
    print()                       # but newline here

或者，您可以使用不带特殊参数的print，并使用numbers将*作为var-arg参数传递。

for name, numbers in fav_numbers.items():
    print(name.title(), *numbers)

这将打印姓名和单个数字，所有数字均用空格分隔。两种方式的输出均为：

Pera 1 6 3 5
Bill 4 6 7 1
Uros 9 0 1 2

Answer 4

format非常适合以特定格式打印

for name,numbers in fav_numbers.items():
    print('{}: {}'.format(name,' '.join((str(n) for n in numbers))))


bill: 4 6 7 1
uros: 9 0 1 2
pera: 1 6 3 5

Answer 5

fav_numbers = {
    'bill': [4,6,7,1],
    'uros': [9,0,1,2],
    'pera': [1,6,3,5],
    }

for name,numbers in fav_numbers.items():
    print(", ".join( repr(e) for e in numbers ).replace(',',''),name)

输出

4 6 7 1 bill
9 0 1 2 uros
1 6 3 5 pera

以end =''打印，格式正确吗？

5 个答案: