How to convert a nested dictionary which contains nested list

Question

I have a nested dictionary that contains (nested lists). I have gone through several posts in the Stackoverflow (here, here, and here). But, I am not getting an idea, how to solve the issues. The dictionary looks like

{ 'LinReg': { 'First': [ array([ 0.83333333, -0.77777778, -0.6       ,  0.72222222]),
                         array([0.4       , 0.05555556, 0.4       , 0.44444444])],
              'Second': [ array([[5.16666667, 3.28571429, 2.4       , 6.38461538]]),
                              array([[ 4.83333333, 23.        ,  1.26666667,  3.22222222]])],
              'Third': [ array([[ 5.16666667, -3.28571429, -2.4       ,  6.38461538]]),
                                     array([[ 4.83333333, 23.        ,  1.26666667,  3.22222222]])],
              'Fourth': [ array([0.83333333, 0.77777778, 0.6       , 0.72222222]),
                                array([0.4       , 0.05555556, 0.4       , 0.44444444])]},
  'kNN': { 'First': [ array([ 0.        , -0.75      ,  0.5       ,  0.41666667]),
                      array([ 0.        , -0.8       , -0.1       ,  0.08333333])],
           'Second': [ array([[1.        , 2.33333333, 4.        , 7.4       ]]),
                           array([[       inf, 2.75      , 1.4       , 1.41666667]])],
           'Third': [ array([[ 0.        , -2.33333333,  4.        ,  7.4       ]]),
                                  array([[ 1.        , -2.75      , -1.4       ,  1.41666667]])],
           'Fourth': [ array([0.        , 0.75      , 0.5       , 0.41666667]),
                             array([0.        , 0.8       , 0.1       , 0.08333333])]}}

The code I am trying

a = ["Album/Track"] + dictionary.keys()
x = list(set([y for z in dictionary.values() for y in z.keys()]))
rows = [a] + [[q] + [dictionary[p].get(q, "-") for p in a[1:]] for q in x]
with open("my.csv", "wb") as csvfile:
    writer = csv.writer(csvfile)
    for row in rows:
        writer.write(row)

How can I convert this dictionary into a CSV file like the below one?

LinReg First Array1_Output1, Array1_Output2, and so on
             Array2_Output1, Array2_Output2, and so on
       Second 
       Third
       Fourth
kNN First Array1_Output1, Array1_Output2, and so on
             Array2_Output1, Array2_Output2, and so on
       Second 
       Third
       Fourth

It is very difficult to answer your question without seeing any of your data nor any of the code that you have written that produces your problem. Please review Jon Skeet's excellent blog post [WRITING THE PERFECT QUESTION](https://codeblog.jonskeet.uk/2010/08/29/writing-the-perfect-question/) for guidance in updating your question. For a more detailed tutorial on asking a good question see Eric S. Raymond's site [How To Ask Questions The Smart Way](http://www.catb.org/~esr/faqs/smart-questions.html) — itprorh66, May 21 '21 at 19:52

score 0 · Answer 1 · answered May 21 '21 at 20:02

0

a_file = open("sample.csv", "w")
a_dict = {Key0: Value0, Key1: Value1....}

writer = csv.writer(a_file)
for key, value in a_dict.items():
    writer.writerow([key, value])

Does this apporach help you? What should the CSV file look like at the end?

answered May 21 '21 at 20:02

Aru

352
1
11

Thank you for your reply. I have updated my questions for the expected output – Opps_0 May 21 '21 at 20:17

score 0 · Accepted Answer · answered May 21 '21 at 20:23

If d is your dictionary from the question, you can do:

import csv

with open("data.csv", "w") as f_in:
    writer = csv.writer(f_in)
    for k, v in d.items():
        for kk, vv in v.items():
            for vvv in vv:
                writer.writerow([k, kk] + list(vvv.ravel()))

Creates data.csv (screenshot from LibreOffice):

How to convert a nested dictionary which contains nested list

2 Answers2