将空值替换为数据框中其他列的值

Question

在我的数据帧的一列中,我有一些空单元格.数据如下所示:

   yymmdd    lat   lon mag depth knmilocatie baglocatie   tijd
 19861226 52.992 6.548 2.8   1.0       Assen      Assen  74751
 19871214 52.928 6.552 2.5   1.5   Hooghalen            204951
 19891201 52.529 4.971 2.7   1.2   Purmerend    Kwadijk 200914
 19910215 52.771 6.914 2.2   3.0       Emmen      Emmen  21116
 19910425 52.952 6.575 2.6   3.0   Geelbroek    Ekehaar 102631
 19910808 52.965 6.573 2.7   3.0     Eleveld      Assen  40114

期望的结果是:

   yymmdd    lat   lon mag depth knmilocatie baglocatie   tijd
 19861226 52.992 6.548 2.8   1.0       Assen      Assen  74751
 19871214 52.928 6.552 2.5   1.5   Hooghalen  Hooghalen 204951
 19891201 52.529 4.971 2.7   1.2   Purmerend    Kwadijk 200914
 19910215 52.771 6.914 2.2   3.0       Emmen      Emmen  21116
 19910425 52.952 6.575 2.6   3.0   Geelbroek    Ekehaar 102631
 19910808 52.965 6.573 2.7   3.0     Eleveld      Assen  40114

受此解决方案的启发,我尝试用以下代码替换空单元格:

df$baglocatie[df$baglocatie == ""] <- df$knmilocatie

然而,这不起作用,因为空单元格填充了错误的值.另一种可能的解决方案也不起作用.

我该如何解决这个问题？

Answer 1

试试ifelse:

df$baglocatie <- ifelse(df$baglocatie == "", df$knmilocatie, df$baglocatie)

Answer 2

您还需要索引替换列：

df[ df$baglocatie == "", "baglocatie"  ]  <- df[ df$baglocatie == "", "knmilocatie" ]