更改索引行数据框

Question

df是数据帧>

i have a dataframe and i want change the names of line index Please guide how I can get this ?

df1=pd.concat(infg)

print df1

        A18         A19         A20  
Peak  213.164273  319.549715  198.585854  
Peak  153.412569  349.485482  145.959831  
Peak  125.797093  358.592932  124.882848  
Peak  198.156800  327.608988  185.250738  
Peak  148.445582  351.232905  141.896721  
Peak  151.817385  346.848871  153.386892  

$我想得到如下结果。你知道吗

   A18         A19         A20  
esp1  213.164273  319.549715  198.585854  
esp2  153.412569  349.485482  145.959831  
esp3  125.797093  358.592932  124.882848  
esp4  198.156800  327.608988  185.250738  
esp5   148.445582  351.232905  141.896721  
esp6  151.817385  346.848871  153.386892  

Answer 1

df1.index = ['esp'+ str(i) for i in range(len(df1.index))]