pandas中多行的按列字符串连接.带有特定分隔符的数据框

Question

是否有有效的方式连接字符串的多行数据帧的列明智，这样的结果是单行，其每列的值是所有给定行的同一列的每个值的连接?

按照上面的解释合并前四行。

>>> df = pd.DataFrame([["this", "this"], ["is", "is"], ["a", "a"], ["test", "test"], ["ignore", "ignore"]])
>>> df
0       1
0    this    this
1      is      is
2       a       a
3    test    test
4  ignore  ignore

均接受结果:

0              1
0  this is a test  this is a test

0
1  this is a test
2  this is a test

Answer 1

如果需要将没有最后使用DataFrame.iloc的所有行与DataFrame.agg连接:

s = df.iloc[:-1].agg(' '.join)
print (s)
0    this is a test
1    this is a test
dtype: object

一行DataFrame加上Series.to_frame的转置:

df = df.iloc[:-1].agg(' '.join).to_frame().T
print (df)
0               1
0  this is a test  this is a test

---

对于所有行:

s = df.agg(' '.join)
print (s)
0    this is a test ignore
1    this is a test ignore
dtype: object

df = df.agg(' '.join).to_frame().T
print (df)
0                      1
0  this is a test ignore  this is a test ignore