如何使用for循环打印字典中包含的列表的元素

Question

我有一本字典：

FFA = {'House': ['0.511', '0.374', 10], 'Chair': ['0.704', '0.381', 10], 'Shoe': ['0.922', '0.465', 10], 'Bottle': ['0.764', '0.348', 10], 'Face': ['1.084', '0.373', 10]}

我想在for循环中打印某些元素：

print "ROI", "Cope", "Mean", "Stddev", "Nsamples"
for k in FFA:
    print "FFA", k, elem[0], elem[1], elem[2]

那是我的输出：

 ROI Cope Mean Stddev Nsamples
FFA House 1.084 0.373 10
FFA Chair 1.084 0.373 10
FFA Shoe 1.084 0.373 10
FFA Bottle 1.084 0.373 10
FFA Face 1.084 0.373 10

但是，我的代码太错了，我找不到在dic中所有键上进行迭代的方法，因此无法正确打印出值。

我希望我的输出是：

ROI Cope Mean Stddev Nsamples
FFA House 0.511 0.374 10
FFA Chair 0.704 0.381 10
FFA Shoe  0.922 0.465 10
FFA Bottle 0.764 0.348 10
FFA Face 1.084 0.373 10

Answer 1

您接近：

print "ROI", "Cope", "Mean", "Stddev", "Nsamples"
for k in FFA:
    elem = FFA[k]
    print "FFA", k, elem[0], elem[1], elem[2]

或直接：

print "ROI", "Cope", "Mean", "Stddev", "Nsamples"
for k in FFA:
    print "FFA", k, FFA[k][0], FFA[k][1], FFA[k][2]

Answer 2

使用items()遍历键和值。 由于您具有多个值，因此可以使用嵌套的for循环遍历多个值来遍历这些值。 对于python 2.x，它将print "FFA", k, values,

print "ROI", "Cope", "Mean", "Stddev", "Nsamples" # Header

for k, v in FFA.items():
    # print ("FFA", k,  end=" ") # For python 3.x
    print "FFA", k,
    for values in v:
        print values,
        # print (values, end=" ") # For python 3.x
    print # To get to print to the new line
    # print ()  # For python 3.x

---

ROI Cope Mean Stddev Nsamples
FFA House 0.511 0.374 10 
FFA Chair 0.704 0.381 10 
FFA Shoe 0.922 0.465 10 
FFA Bottle 0.764 0.348 10 
FFA Face 1.084 0.373 10 

Answer 3

您已经遍历了键，现在只需要遍历值的元素：

FFA = {'House': ['0.511', '0.374', 10], 
       'Chair': ['0.704', '0.381', 10], 
       'Shoe': ['0.922', '0.465', 10], 
       'Bottle': ['0.764', '0.348', 10], 
      'Face': ['1.084', '0.373', 10]} 

print "ROI", "Cope", "Mean", "Stddev", "Nsamples"


for k in FFA:      # loop over keys in dict 
    print "FFA", k,     # , at end == no newline
    for elem in FFA[k]: # loop over values in list of key
        print elem,         # , at end == no newline
    print               # now a newline

输出：

ROI Cope Mean Stddev Nsamples
FFA House 0.511 0.374 10
FFA Chair 0.704 0.381 10
FFA Shoe 0.922 0.465 10
FFA Bottle 0.764 0.348 10