Pandas 替换在一行中有效，但在另一行中无效

Question

I'm trying to clean some data (Python 3.7.3) and was able to replace NaN values with empty strings using

def g(x):
    return pd.Series(x.replace(np.nan, ""))
df = df.apply(g)

and get the desired output:

1    2      3            4
qt>  qml>   tableview>

etc, but then I tried to do something similar to replace the ">" with an empty string

def h(x):
   return pd.Series(x.replace(">", ""))
df = df.apply(h)

but the dataframe doesn't change and I still have the ">" at the end of each word. No errors are thrown at me, so I'm at a loss. Thanks in advance for any answers

Answer 1

Replace your h function with:

def h(x):
   return pd.Series(x.str.replace(">", ""))
df = df.apply(h)

Answer 2

def h(x):
      return x.replace(">", "",regex=True)
df = df.apply(h)

Answer 3

Please try the following:

def g(x):
    return pd.Series(x.replace(">", "",regex=True))
df = df.apply(g)  

This should work.