如何使用for循环打印字典中包含的列表的元素

Question

I have a dictionary:

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]}

I want to print certain elements in a for loop:

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

That's my output:

 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

However, my code is so wrong I can't find a way of iterating over all the keys in the dic so the right values are printed out.

I want my output to be:

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

You were close:

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

or directly:

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

Answer 2

Use items() to iterate over the keys and the values. Since you have multiple values, iterate over the values using the nested for loop over multiple values. For python 2.x it will be 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

You already loop over the keys, now you simply need to loop over the elements of the values:

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

Output:

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