Replace Values with NA by same position in another df

Question

I have two dataframes:

df1
 Col1     Col2      Col3     Col4
    1        0         3        5 
   NA        1        NA        0
    2        3        NA        5

df2
 Col1     Col2      Col3     Col4
    7        0         5        7 
    0        8         0        0
    9        9         6        2

How do I replace df2 with NA's by same position of df1?

I want my final df3 to look like this:

 Col1     Col2      Col3     Col4
    7        0         5        7 
   NA        8        NA        0
    9        9        NA        2

Related / possible duplicate: [*How do I replace NA values with zeros in an R dataframe?*](https://stackoverflow.com/q/8161836/2204410) — Jaap, Jun 12 '18 at 18:54

Jaap · Accepted Answer · 2018-06-12T19:29:43.870

3

In my opinion base R is better equiped for that compared to the tidyverse:

df2[is.na(df1)] <- NA

which gives:

> df2
  Col1 Col2 Col3 Col4
1    7    0    5    7
2   NA    8   NA    0
3    9    9   NA    2

And if you really need df3:

df3 <- df2
df3[is.na(df1)] <- NA

edited Jun 12 '18 at 19:29

answered Jun 12 '18 at 18:50

Jaap

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score 0 · Answer 2 · answered Jun 12 '18 at 18:53

0

df3=`is.na<-`(df2,is.na(df1))
df3
  Col1 Col2 Col3 Col4
1    7    0    5    7
2   NA    8   NA    0
3    9    9   NA    2

or even

df3=replace(df2,is.na(df1),NA)
 df3
  Col1 Col2 Col3 Col4
1    7    0    5    7
2   NA    8   NA    0
3    9    9   NA    2

answered Jun 12 '18 at 18:53

Onyambu

67,392
3
24
53

1

note that `replace` is nothing more than a wrapper aroud `x[condition] <- value` – Jaap Jun 12 '18 at 19:07
@jaap with your solution, you are making a copy of the dataframe.. while this has no copy made. – Onyambu Jun 12 '18 at 19:11

Replace Values with NA by same position in another df

2 Answers2