What is the most efficient way to reshape a dataframe

Question

Given the following dataframe:

Number    Color1    Color2
 1         Red      Yellow
 2         Green    Blue

How can I reshape this dataframe around the "Number" column?

Expected output

Number    Color
  1        Red
  1        Yellow
  2        Green
  2        Blue

Note: The column names may not always be similar (Color1 and Color2 could be anything and aren't related)

`df.set_index('Number').stack().reset_index(drop=True, level=1)` — rafaelc, Sep 23 '19 at 17:53

score 0 · Answer 1 · answered Sep 23 '19 at 17:54

score 0 · Answer 2 · answered Sep 23 '19 at 17:55

0

df.set_index('Number').stack().reset_index(drop=True, level=1)?

answered Sep 23 '19 at 17:55

hd1

Here are some guidelines for [How do I write a good answer?](https://stackoverflow.com/help/how-to-answer). This provided answer may be correct, but it could benefit from an explanation. Code only answers are not considered "good" answers. From [review](https://stackoverflow.com/review). – Trenton McKinney Sep 24 '19 at 00:46

2 Answers2