Phil, What have you tried. This seems straightforward enough.
Could you clarify what you mean by NULL? In R, it is common to use NA or a more specific version of it. So assuming you have two vectors containing floats with some NA, then: C <- A*B Will give you the products one at a time if the lengths are the same. NA times anything is NA. Your second condition is also simple as you want anything below a threshold to be set to a fixes value. Since you already have C, above, your condition of: threshold <- 0.1 C < threshold The last line returns a Boolean vector you can use to index C to get just the ones you select as TRUE and thus can change: Result <- C[C < threshold] And you can of course do all the above as a one-liner. Is that what you wanted? -----Original Message----- From: R-help <r-help-boun...@r-project.org> On Behalf Of Philip Rhoades via R-help Sent: Tuesday, June 20, 2023 11:38 AM To: r-help@r-project.org Subject: [R] Multiplying two vectors of the same size to give a third vector of the same size People, I am assuming that what I want to do is easier in R than say Ruby. I want to do what the Subject says ie multiply the cells in the same position of two vectors (A and B) to give a result in the same position in a third vector (C) BUT: - The values in the cells of A and B are floats between 0.0 and 1.0 or NULL - If there is a NULL in the multiplication, then the result in the cell for C is also a NULL - If there is a value less than (say) 0.01 in the multiplication, then the result in the cell for C is 0.0 Any suggestions appreciated! Phil. -- Philip Rhoades PO Box 896 Cowra NSW 2794 Australia E-mail: p...@pricom.com.au ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
