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..., dataset=1) * (biomass at date 2 -biomass at date 1, dataset = 2) + (littfall at date 2, dataset=3). all the dates are in yr-month-day format. Which library or function Should I use to tell R do these calculations of these variables at different dates. I appreciate your help. Ahmed Attia, Ph.D. Agronomist & Soil Scientist

...Necesito saber si alguien tiene alguna idea de un paquete con múltiples funciones (cálculos) para determinar el tamaño de la muestra (particularmente de estudios de psicología y ciencias sociales). De antemano agradezco la atención. Saludo desde Brasil *Guilherme Amorim Homem de Abreu Loureiro* Agronomist Engineer *CREA-BA: 051511013-2* Master of Science in Crop Production, Soil and Plant Nutrition *55 27 996215348 / 55 73 991934645* *Itabuna - Bahia - Brazil* [[alternative HTML version deleted]]

...ta=Stand_Height)); dl=leafbiom$Date[i-1]; de=leafbiom$Date[i]; SH[i]=sum(SH[leafbiom$Date==de&leafbiom$Date==dl]) } SH The SH output is the prediction of Stand height in 25 observations only and provides NA for the remaining 2616 iterations. Thanks for your help. Ahmed Attia, Ph.D. Agronomist & Soil Scientist

The model should be class aov or lm and my model class is aovlist. tried tidy from broom library but did not work. To make it class aov, I had to remove the error term; model <- aov(Rotationdata_R$`GY(Mg/ha)`~Rep+code*as.factor(Nitrogen),data=Rotationdata_R) Ahmed Attia, Ph.D. Agronomist & Soil Scientist On Mon, Dec 25, 2017 at 7:38 PM, David Winsemius <dwinsemius at comcast.net> wrote: > >> On Dec 25, 2017, at 10:21 AM, Ahmed Attia <ahmedatia80 at gmail.com> wrote: >> >> LSD.test > > ?LSD.test > No documentation for ?LSD.test? in...

...at date 1, dataset = 2) + (littfall at date 2, dataset=3). > > all the dates are in yr-month-day format. Which library or function > Should I use to tell R do these calculations of these variables at > different dates. > > I appreciate your help. > > Ahmed Attia, Ph.D. > Agronomist & Soil Scientist > > ______________________________________________ > R-help at 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 provid...

...;p",cex=0.2,col=1,xaxs="i",yaxs="i",ylim=c(0,6)) axis.Date(side=3, at=seq(min(LAI_simulation$Date), max(LAI_simulation$Date),by="year"), format="%Y", xlab="xxx",cex.axis=0.9) mtext("years",side=3,line=3,cex.lab=1.2) Ahmed Attia, Ph.D. Agronomist & Soil Scientist On Wed, Jul 5, 2017 at 4:52 PM, MacQueen, Don <macqueen1 at llnl.gov> wrote: > Not entirely sure what you really want the axis on the top to look like, but here's what I'd be likely to do: > > ## note, correction to format; in your example data year...

...= 2016, frequency =365) plot(forecast(ets(Stand_Height),10)) a=seq(as.Date("2009-12-01"),by="weeks",length=11) axis(1, at = a, labels = format(a, "%Y %b %d"), cex.axis=0.6) #Error :$ operator is invalid for atomic vectors Thanks Ahmed Attia, Ph.D. Agronomist & Soil Scientist On Fri, Jun 30, 2017 at 10:37 AM, Sarah Goslee <sarah.goslee at gmail.com> wrote: > There are a bunch of things wrong here, although without a > reproducible example I can't really fix most of them. > > - You're overwriting SH within the loop. &g...

...SH[i]=sum(SH[leafbiom$Date==de&leafbiom$Date==dl]) > > > } > SH > > > The SH output is the prediction of Stand height in 25 observations > only and provides NA for the remaining 2616 iterations. > > Thanks for your help. > > > > Ahmed Attia, Ph.D. > Agronomist & Soil Scientist > -- Sarah Goslee http://www.functionaldiversity.org

...83.99995 (xmin, xmax, ymin, ymax) > coord. ref. : +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 > +towgs84=0,0,0 > data source : C:\Users\Ahmed\Documents\file.tif > names : file > values : 2, 80 (min, max) > > Any help! > > > Ahmed Attia, Ph.D. > Agronomist & Soil Scientist > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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://ww...

...eatment. - Data should be considered as repeated measurements over time (years)? In multcomp package: - What is the equivalence between the tests proposed ("Sequen", "AVE", "Changepoint", "Williams", "Marcus", "McDermott") and the tests agronomist are used to do: LSD (least significant difference), Duncan multiple range test, Scheffe, S-N-K (Student-Newman-Keuls)? Thanks a lot for your interest. Jorge Lampurlan?s Agronomist >> Is it possible to do this analysis in R? > > Yes, it is possible. The syntax isn't in place ye...

...SD.test(y=model,trt="code",console=TRUE) the error; Error in as.data.frame.default(x[[i]], optional = TRUE, stringsAsFactors = stringsAsFactors) : cannot coerce class "c("aovlist", "listof")" to a data.frame What is wrong with this. Ahmed Attia, Ph.D. Agronomist & Soil Scientist

...did not work. To make it class aov, > I had to remove the error term; > > model <- aov(Rotationdata_R$`GY(Mg/ha)`~Rep+code*as.factor(Nitrogen),data=Rotationdata_R) You seemed to have missed my point that LSD.test is not in the packages loaded by default. > Ahmed Attia, Ph.D. > Agronomist & Soil Scientist > > > > > > > On Mon, Dec 25, 2017 at 7:38 PM, David Winsemius <dwinsemius at comcast.net> wrote: >> >>> On Dec 25, 2017, at 10:21 AM, Ahmed Attia <ahmedatia80 at gmail.com> wrote: >>> >>> LSD.test >&g...

...0.009998 LAI_simulation$Date <- as.Date( LAI_simulation$Date, '%Y/%m/%d') plot(LAI~Date, data=LAI_simulation) LAI_simulation$Date<- as.numeric(LAI_simulation$Date,origin="2009-10-07") #R does not see the origin axis.Date(side=3,at=LAI_simulation$Date) Ahmed Attia, Ph.D. Agronomist & Soil Scientist [[alternative HTML version deleted]]

...1"]+ Litterfall_Ahmed97$littperiod[Litterfall_Ahmed97$Date =="i"])/ (sum(GPP_Ahmed13$GPP[GPP_Ahmed13$Date >= "i-1" & GPP_Ahmed13$Date <= "i"])/2) } #Error in charToDate(x) : Thanks for your help Ahmed Attia, Ph.D. Agronomist & Soil Scientist

In the model: lm.1 <- lm(variable ~ BLOC + TIL * YEAR , data=selvanera) I found TIL*YEAR interaction significant. Then I am trying to compare means of the different levels of TIL inside every YEAR using: mc.2 <- glht(lm.1, linfct = mcp(TIL*YEAR="Tukey")) summary(mc.2, test = univariate()) but it does not work. There is any way of doing this, like the SLICE option in

S??ren H??jsgaard wrote: > Dear all, > I have used R (Windows) for teaching statistics to agronomists and biologists - and they love R!! Yet there is one immediate short coming of R: The lack of an integrated editor. A plain editor (e.g. similar to notepad in windows) in which people can write their code, highlight the piece of code they wish to "submit" and then press a single key to ha...

..., 0.00833333 (x, y) extent : -180, 179.9998, -56, 83.99995 (xmin, xmax, ymin, ymax) coord. ref. : +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0 data source : C:\Users\Ahmed\Documents\file.tif names : file values : 2, 80 (min, max) Any help! Ahmed Attia, Ph.D. Agronomist & Soil Scientist [[alternative HTML version deleted]]

...cast(ets(Stand_Height),10)) > a=seq(as.Date("2009-12-01"),by="weeks",length=11) > axis(1, at = a, labels = format(a, "%Y %b %d"), cex.axis=0.6) > > > #Error :$ operator is invalid for atomic vectors > > Thanks > > > Ahmed Attia, Ph.D. > Agronomist & Soil Scientist > > > > > > > On Fri, Jun 30, 2017 at 10:37 AM, Sarah Goslee <sarah.goslee at gmail.com> wrote: >> There are a bunch of things wrong here, although without a >> reproducible example I can't really fix most of them. >> >> -...

As an agronomist, sometimes i need to perform statistical analisys on "weird" field data, like 3 or 4 level split plot design. I've read both the help of the program, some books and manual about S and "Venables/Ripley, Modern Applied Statistics with S", but i still have problems in (i su...

As an agronomist, sometimes i need to perform statistical analisys on "weird" field data, like 3 or 4 level split plot design. I've read both the help of the program, some books and manual about S and "Venables/Ripley, Modern Applied Statistics with S", but i still have problems in (i su...