[R] Producing a table with mean values

[arun]

HI John,

I got it.  Please disregard my previous email.
I guess the code should be:

tabx <-  ddply(meltx, .(Seamount, variable),  summarize, mean = mean(value), sd = sd(value))


A.K.

----- Original Message -----
From: John Kane <jrkrideau at inbox.com>
To: Tinus Sonnekus <tsonnekus at gmail.com>; r-help at r-project.org
Cc: 
Sent: Saturday, September 8, 2012 1:19 PM
Subject: Re: [R] Producing a table with mean values

x  <-   " Seamount     Pico    Nano   Micro    Total_Ch
Off_Mount1 0.0691 0.24200 0.00100  0.31210
Off_Mount1 0.0938 0.00521 0.02060  0.11961
Off_Mount1 0.1130 0.20000 0.06620  0.37920
Off_Mount1 0.0864 0.15900 0.22300  0.46840
Off_Mount1 0.0262 0.04570 0.00261  0.07451
Off_Mount2 0.0314 0.17400 0.12800  0.33340
Off_Mount2 0.0314 0.17400 0.12800  0.23340
Off_Mount2 0.0414 0.17400 0.02800  0.23340"

xx <- read.table(textConnection(x), header=TRUE, as.is=TRUE)

library(reshape)
meltx  <-  melt(xx)

tabx <-  ddply(nn, .(Seamount, variable),  summarize, mean = mean(value), sd = sd(value))

tabx

John Kane
Kingston ON Canada


> -----Original Message-----
> From: tsonnekus at gmail.com
> Sent: Fri, 7 Sep 2012 22:49:55 +0200
> To: r-help at r-project.org
> Subject: [R] Producing a table with mean values
> 
> Hi All,
> 
> I have a data set wit three size classes (pico, nano and micro) and 12
> different sites (Seamounts). I want to produce a table with the mean and
> standard deviation values for each site.
> 
>      Seamount     Pico    Nano   Micro    Total_Ch
> 1 Off_Mount 1 0.0691 0.24200 0.00100  0.31210
> 2 Off_Mount 1 0.0938 0.00521 0.02060  0.11961
> 3 Off_Mount 1 0.1130 0.20000 0.06620  0.37920
> 4 Off_Mount 1 0.0864 0.15900 0.22300  0.46840
> 5 Off_Mount 1 0.0262 0.04570 0.00261  0.07451
> 6 Off_Mount 2 0.0314 0.17400 0.12800  0.33340
> 
> I tried the following script but get an error message
> 
> *Error in results[i, "u.Pico", "u.Nano", "u.Micro"] <- sapply(z, mean) :
> *
> *  incorrect number of subscripts *
> 
> The code I used:
> 
> *SChla <- read.csv("SM_Chla_data.csv")*
> *sm <- as.character(unique(SChla$Seamount))*
> *
> *
> *results <-
> matrix(NA,nrow=length(sm),ncol=6,dimnames=list(sm,c("u.Pico","u.Nano","u.Micro","sd.Pico","sd.Nano","sd.Micro")))
> *
> *
> *
> *for (i in sm){*
> *z <- subset(SChla, Seamount==i, select=c(Pico, Nano, Micro))*
> *results[i,"u.Pico","u.Nano","u.Micro"] <- sapply(z, mean)*
> *results[i,"sd.Pico","sd.Nano","sd.Micro"] <- sapply(z, sd)*
> *}*
> *
> *
> *print(results)*
> 
> Please can some one advise me how to fix the error or maybe have an
> alternative solution I will appreciate it.
> 
> Thank you.
> Tinus
> 
>     [[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org mailing list
> 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.

____________________________________________________________
GET FREE SMILEYS FOR YOUR IM & EMAIL - Learn more at http://www.inbox.com/smileys
Works with AIM®, MSN® Messenger, Yahoo!® Messenger, ICQ®, Google Talk™ and most webmails

______________________________________________
R-help at r-project.org mailing list
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.