Pandas Dataframe为键值对和csv格式

Question

I have a dataframe like below.

df1 = pd.DataFrame({'a': [1, 20],
                    'b': [10, 200],
                'c': [100, 300]})
print(df1)


    a    b    c
0   1   10  100
1  20  200  300

I want to have it in these 2 formats - Format 1-

0, a, 1
0, b, 10
0, c, 100

1, a, 20
1, b, 200
1, c, 300

Format 2-

a=1
b=10
c=100

a=20
b=200
c=300

I could convert to dict and do some iteration but not sure if that is the best approach.

df1.to_dict()
{'a': {0: 1, 1: 20}, 
 'b': {0: 10, 1: 200}, 
 'c': {0: 100, 1: 300}
}

How can i change this -

0       a=1
1     b=10
2    c=100
3     a=20
4    b=200
5    c=300

back to

        a    b    c
   0   1   10  100
   1  20  200  300

Answer 1

IIUC, since the column name is not important to u, I a not change it

s=df1.stack().reset_index()
s
Out[140]: 
   level_0 level_1    0
0        0       a    1
1        0       b   10
2        0       c  100
3        1       a   20
4        1       b  200
5        1       c  300
New=s.level_1+'='+s[0].astype(str)
New
Out[142]: 
0      a=1
1     b=10
2    c=100
3     a=20
4    b=200
5    c=300
dtype: object

Convert it back

s=s.str.split('=',expand=True)

s.assign(i=s.groupby(0).cumcount()).pivot('i',0,1)
Out[208]: 
0   a    b    c
i              
0   1   10  100
1  20  200  300