我想在数据帧的所有列中仅加上负数。

我看过这篇文章：pandas：将多列列入一列

我的数据如下：

+----------------+--------------------+---------------------+--------------------+---------------------+---------------------+---------------------+---------------------+---------------------+

| account_number | BARCL | BNPFX | FXBOA | GOLDM | HSBCFX | JPMORB | MSFX | UBSFX |

+----------------+--------------------+---------------------+--------------------+---------------------+---------------------+---------------------+---------------------+---------------------+

| 1 | | | | 0.0 | | | | |

| 5 | | | 706369.7735466702 | -2162385.1089132824 | 3786856.0528284833 | -95282.82681401384 | -193996.63423402887 | |

| 10 | | -1394033.7621652137 | | 14898.298674858579 | -58424.08672944151 | 6371473.519703947 | 173216.43850648316 | 65139.81953726128 |

| 30 | | | | 4184.360535274067 | | | | |

| 40 | 129241.81676740313 | -47653.12899072186 | -28560.75186645159 | 2064798.5883593727 | -5443781.727655317 | -889622.1548077458 | -89766.77039075969 | 2662058.075519108 |

| 60 | 12382.163467076947 | -339976.8400535829 | 4901.134360516224 | 515432.2325989893 | 1094.7041191283581 | -154589.57521740254 | 11682.303417535806 | -23401.914319010615 |

| 70 | | -172.08916638212867 | 108.35243809241544 | 2611.854248265494 | -7063.2001690974175 | -9709.704382280293 | | |

| 90 | | | | -1783103.2174374713 | 10576.903475689503 | -71848.48303512641 | | |

+----------------+--------------------+---------------------+--------------------+---------------------+---------------------+---------------------+---------------------+---------------------+

但我想仅总结负数。我怎么做？

解决办法：运用 mask

df.iloc[:,1:].where(df.iloc[:,1:]<0).sum(axis=1)