How to change specific values in a pandas dataframe?-CodePudding

I have the following dataframe:

d = {'col1':['b',''], 'col2':['','a'], 'col3':['','']}
index = ['name1','name2']
df = pd.DataFrame(index=index, data=d)
df

        col1    col2    col3
name1   b       
name2           a

My goal is to have something like this:

        col1    col2    col3
name1   green   red     yellow
name2

I need help with the logic of renaming the columns.

Rename only row 1.

if a-z in row 1 than 'green'

elif a-z in row 2 than 'red'

elif both rows empty than 'yellow'

What I tried is the following, but it only changes one color.

df.replace({'[a-z]':'green'},regex=True)

Could anyone help me solve this problem?

CodePudding user response：

Use:

a = df.loc['name1'].replace({'[a-z]':'green', '':np.nan},regex=True)
b = df.loc['name2'].replace({'[a-z]':'red', '':np.nan},regex=True)

df.loc['name1'] = a.fillna(b).fillna('yellow')
print (df)
        col1 col2    col3
name1  green  red  yellow
name2           a    

df.loc['name2','col2'] = ''
print (df)
        col1 col2    col3
name1  green  red  yellow
name2