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Finding Maximum Row Element Across 3 Columns

I'm sorry to have to ask for help to solve this very basic R problem.

I have a table from which I want to find the maximum values across the first 3 columns:

 Col1    Col2    Col3    Col4
   2    4    5    3
  17    2    30    21
   5    4    2    7
   8    19    1    0

The max values are outputted in Col1 and bound to Col4 values in a new table thus:

Col1    Col4
 5    3
30    21
 5    7
19    0

I have tried:

Col1 <- apply(Table1, 1, 'max')

Which did not work exactly as required. Help will be appreciated.

r bioconductor
• 7,767 views • link
updated by Charles Warden Charles Warden • written by robjohn7000 robjohn7000

This is a basic R programming question. Please explain its relevance to a bioinformatics research problem.

• 167 views • link
written by Neilfws Neilfws

1 answer

Create two separate data frames first,with columns 1:3 and 4:ncol(Table1).

You can use apply on the first 3 columns and then add the result to the second data frame (either by creating a new data frame or using cbind)

• 186 views • link
written by Charles Warden Charles Warden

Thank you cwardens45! That solved the problem.

• 0 views • link
written by robjohn7000 robjohn7000

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