Message-ID: <1db72680050524073651078cd@mail.gmail.com>
Date: 2005-05-24T14:36:25Z
From: roger bos
Subject: Basic matematical functions with NAs
In-Reply-To: <003001c56085$38ea1930$f10aa8c0@paulobrando>
Simple, all those functions, such as sum(), colSums(), colMeans(),
etc. have an argument called na.rm which you can set to TRUE to remove
NAs.
so try something like sum(X, na.rm=TRUE)
HTH,
Roger
On 5/24/05, Paulo Brando <pmbrando at ipam.org.br> wrote:
> Dear All,
>
> I've tried to sum columns -- different species of flowers, fruits plus twigs -- with NAs to get litterfall/trap, and then after use litterfall to calculate production (litterfall (grams)/ hectare/ day. But R 'sees' litterfall/trap as a string.
>
> My question: How to use basic mathematical functions to deal with NAs in data management.
>
> Example (as you can note I have many missing values -- no fruit fell in the trap.
>
>
> area ponto date pseco psaco pliquido florg1 flor1 florg2 flor2 florg3 flor3 frutog1 fruto1 frutog2 fruto2 frutog3 fruto3 frutog4 fruto4 frutog5 fruto5 frutog6 fruto6 frutog7 fruto7 frutog8 fruto8 twigs
> A A 1 38233 17.7 1.6 7.1 0.266 1
> A AA 1 38233 12.5 8.7 3.8
> A AB 1 38233 13.9 1.7 3.2 0.421 3
> A B 1 38233 12.1 1.6 1.5 0.248 2 0.435 7 0.16 1
> A BORDA 1 38233
> A C 1 38233 15.6 1.7 4.9 0.374 2 0.298 3 0.231 1
> A F 1 38233 14 1.5 3.5 0.366 45 0.153 1 0.15 1
>
>
>
> Paulo Brando
> Inst. de Pesquisa Ambiental da Amaz??nia (IPAM)
> Rua Rui Barbosa,136.
> 68.005.080 Santar??m, PA, Brazil.
> Fone/Fax ++ 55 93 522 5538
> www.ipam.org.br
> [[alternative HTML version deleted]]
>
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