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How can I know how many values are NA in a dataset? OR if there are any NAs and NaNs in dataset?

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    `anyNA`, `complete.cases`, and `na.omit` are all useful functions. Your question is not very specific and clearly off-topic. – Roland Mar 16 '15 at 10:59
  • There is not function named anyNA in R. Can you tell me how you used it? –  Mar 16 '15 at 11:06
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    If there is no `anyNA` in your R version, you should update R. – Roland Mar 16 '15 at 11:48
  • I'm voting to close this question as off-topic because it is a basic question about using R. See advice on software-related questions in the Help Center. – Nick Cox Mar 16 '15 at 12:11
  • I'm voting to close this question as off-topic because it is about how to use r without a reproducible example. – gung - Reinstate Monica Mar 16 '15 at 12:11
  • Does this answer your question? [Determine the number of NA values in a column](https://stackoverflow.com/questions/24027605/determine-the-number-of-na-values-in-a-column) – UseR10085 May 23 '20 at 10:03

4 Answers4

12

This may also work fine 

sum(is.na(df)) #  For entire dataset

for a particular column in a dataset

sum(is.na(df$col1))

Or to check for all the columns as mentioned by @nicola

colSums(is.na(df))
Magma
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Deepesh
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2

As @Roland noticed there are multiple functions for finding and dealing with missing values in R (see help("NA") and here).

Example:

Create a fake dataset with some NA's:

data <- matrix(1:300,,3)
data[sample(300, 40)] <- NA

Check if there are any missing values:

anyNA(data)

Columnwise check if there are any missing values:

apply(data, 2, anyNA)

Check percentages and counts of missing values in columns:

colMeans(is.na(data))*100
colSums(is.na(data))
Tim
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0

For a dataframe it is:

sum(is.na(df)

here df is the dataframe

where as for a particular column in the dataframe you can use:

sum(is.na(df$col)

or

cnt=0

for(i in df$col){
if(is.na(i)){
    cnt=cnt+1
  }
}
cnt

here cnt gives the no. of NA in the column

Jayanth
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0

You can simply get the number of "NA" included in the each column of dataset by using R.

For a vector x

summary(x)

For a data frame df

summary(df)
7-x
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