I want to rename rows in python program (version - spyder 3
- python 3.6
) . At this point I have something like that:
import pandas as pd
data = pd.read_csv(filepath, delim_whitespace = True, header = None)
Before that i wanted to rename my columns:
data.columns = ['A', 'B', 'C']
It gave me something like that.
A B C
0 1 n 1
1 1 H 0
2 2 He 1
3 3 Be 2
But now, I want to rename rows. I want:
A B C
n 1 n 1
H 1 H 0
He 2 He 1
Be 3 Be 2
How can I do it? The main idea is to rename every row created by pd.read
by the data in the B column. I tried something like this:
for rows in data:
data.rename(index={0:'df.loc(index, 'B')', 1:'one'})
but it's not working.
Any ideas? Maybe just replace the data frame rows by column B? How?
I think need set_index
with rename_axis
:
df1 = df.set_index('B', drop=False).rename_axis(None)
Solution with rename
and dictionary:
df1 = df.rename(dict(zip(df.index, df['B'])))
print (dict(zip(df.index, df['B'])))
{0: 'n', 1: 'H', 2: 'He', 3: 'Be'}
If default RangeIndex
solution should be:
df1 = df.rename(dict(enumerate(df['B'])))
print (dict(enumerate(df['B'])))
{0: 'n', 1: 'H', 2: 'He', 3: 'Be'}
Output:
print (df1)
A B C
n 1 n 1
H 1 H 0
He 2 He 1
Be 3 Be 2
EDIT:
If dont want column B
solution is with read_csv
by parameter index_col
:
import pandas as pd
temp=u"""1 n 1
1 H 0
2 He 1
3 Be 2"""
#after testing replace 'pd.compat.StringIO(temp)' to 'filename.csv'
df = pd.read_csv(pd.compat.StringIO(temp), delim_whitespace=True, header=None, index_col=[1])
print (df)
0 2
1
n 1 1
H 1 0
He 2 1
Be 3 2