how to call a function for each row

Isn't this even easier?
X1 <- c(1:3)
X2 <- c(3, 4, 6)
X3 <- c(5, 6, 1)
Y <- 6*X1 + 7*X2 + 8*X3
Y
[1] 67 88 68

Or if you really need a function:
MakeY <- function(x, y, z) 6*x + 7*y + 8*z
MakeY(X1, X2, X3)
[1] 67 88 68

----------------------------------------------
David L Carlson
Associate Professor of Anthropology
Texas A&M University
College Station, TX 77843-4352

-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On
Behalf Of R. Michael Weylandt
Sent: Wednesday, November 30, 2011 8:17 AM
To: arunkumar1111
Cc: r-help at r-project.org
Subject: Re: [R] how to call a function for each row

Read ?apply

This is easiest:

df <- matrix(c(1,2,3,3,4,6,5,6,1), 3)
apply(df, 1, function(x) 6*x[1]+7*x[2]+8*x[3])

But it's much more efficient to do it with matrix multiplication. In keeping
with the best of tradition, this is left as an exercise to the reader.

Michael
Hi

?I have ?a data-frame which look like this

X1 X2 X3
1 ? 3 ?5
2 ? 4 ?6
3 ? 6 ?1

I want to apply a formula Y=6*X1 + 7*X2 + 8*X3 ?for every row

Thanks in Advance

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how to call a function for each row

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