我正在使用熊猫,所以基本上我有两个数据帧,并且在两种情况下的行数都不同:
东风
wave num stlines fwhm EWs MeasredWave
0 4050.32 3 0.28269 0.07365 22.16080 4050.311360
1 4208.98 5 0.48122 0.08765 44.90035 4208.972962
2 4374.94 9 0.71483 0.11429 86.96497 4374.927110
3 4379.74 9 0.31404 0.09107 30.44271 4379.760601
4 4398.01 14 0.50415 0.09845 52.83236 4398.007473
5 5520.50 1 0.06148 0.12556 8.21685 5520.484742
DF1
wave num stlines fwhm EWs MeasredWave
0 4050.32 3 0.28616 0.07521 22.91064 4050.327388
1 4208.98 6 0.48781 0.08573 44.51609 4208.990029
2 4374.94 9 0.71548 0.11437 87.10152 4374.944513
3 4379.74 10 0.31338 0.09098 30.34791 4379.778009
4 4398.01 15 0.49950 0.08612 45.78707 4398.020367
5 4502.21 9 0.56362 0.10114 60.67868 4502.223123
6 4508.28 3 0.69554 0.11600 85.88428 4508.291777
7 4512.99 2 0.20486 0.08891 19.38745 4512.999332
8 5520.50 1 0.06148 0.12556 8.21685 5520.484742
所以df1
中有一些行不在df
.所以我想将行添加到数据帧并相应地重置索引。以前我只是从数据帧中删除多余的行以使它们相等,但现在我只想添加列索引不存在的空行。
所需的结果应如下所示,
wave num stlines fwhm EWs MeasredWave
0 4050.32 3 0.28269 0.07365 22.16080 4050.311360
1 4208.98 5 0.48122 0.08765 44.90035 4208.972962
2 4374.94 9 0.71483 0.11429 86.96497 4374.927110
3 4379.74 9 0.31404 0.09107 30.44271 4379.760601
4 4398.01 14 0.50415 0.09845 52.83236 4398.007473
5 4502.21 0 0 0 0 0
6 4508.28 0 0 0 0 0
7 4512.99 0 0 0 0 0
8 5520.50 1 0.06148 0.12556 8.21685 5520.484742
我怎样才能得到这个?
IIUC,您可以使用DataFrame.loc
来更新df
中不存在wave
的df1
的值:
df1.loc[~df1.wave.isin(df.wave), 'num':] = 0
然后使用DataFrame.combine_first
确保df
中的值优先:
df_out = df.set_index('wave').combine_first(df1.set_index('wave')).reset_index()
[出]
print(df_out)
wave num stlines fwhm EWs MeasredWave
0 4050.32 3.0 0.28269 0.07365 22.16080 4050.311360
1 4208.98 5.0 0.48122 0.08765 44.90035 4208.972962
2 4374.94 9.0 0.71483 0.11429 86.96497 4374.927110
3 4379.74 9.0 0.31404 0.09107 30.44271 4379.760601
4 4398.01 14.0 0.50415 0.09845 52.83236 4398.007473
5 4502.21 0.0 0.00000 0.00000 0.00000 0.000000
6 4508.28 0.0 0.00000 0.00000 0.00000 0.000000
7 4512.99 0.0 0.00000 0.00000 0.00000 0.000000
8 5520.50 1.0 0.06148 0.12556 8.21685 5520.484742