similar to: using subset

Hi, I'd like to find which values of x will give me a y. In other words, in the example of a gaussian curve, I want to find the values of x that will give me a density, let's say, of 0.02. curve(((1/(sqrt(2*pi)*10))*exp(-((x-50)^2)/(2*10^2))),xlim=c(0,100)) Thanks for any help, Antonio Olinto ------------------------------------------------- WebMail Bignet - O seu provedor do

Hi, I want to write in x axis label "fitted value of lambda" (lambda in greek letter). xlab=expression(lambda) gives the "lambda", I tryed things like xlab=paste ("fitted value of ", expression(lambda)) but I didn't get the greek letter. Thanks in advance for any hint. Antonio Olinto ------------------------------------------------- WebMail Bignet - O seu

Hello all, Here goes one of my first functions. I want to make a nonparametric multiple sample comparison with unequal sample sizes (see Zar?s Biostatistical Analysis, 3rd. Ed., pg. 201 Example 10.11, pg. 288 Example 11.10). In the real world, I want to compare samples of fish length captured with different fishing gears. After using the Kruskal-Wallis test I want to check the differences

Hi, I have a dataframe with 3 columns: month (1 to 12), length and length class. I'm trying to make a cross table with the counts of lengths per length class and month. I don??t have all classes per month. | 1 2 3 ... ------------- 120 | 0 1 0 150 | 5 6 0 170 | 3 0 7 ... I have already tryed many commands, without success - unfortunately. May someone help me? Thanks in advance!

Hello, I have a doubt in using the function step (step wise) to select glm models. Usually I apply the gamma distribution to analyze fishery data. To select the terms I use a routine where I first compare single term models to the null model (eg. U~1 vs. U~depth; U~1 vs. U~latitude; etc. ? where U= abundance) and, by means of the result given by a likelihook function applied for each comparison,

Hello, This is my first post to this list. Well, I tried to install Google Earth using WineTools but I got the "Unknown Graphics Card" error. I can open the program but Earth doesn't appear. I'm running Debian Sarge on a ASUS CUW(E)-FX motherboard (Intel 810 Chipset) and Gnome 2.10.2 inteface. Thanks for any help. Best regards, Antonio -- Ant?nio Olinto Biologist /

Hi, I?m trying to make a barplot with the following dataframe, with information on relative frequency per sediment type (ST) for some species: Species ST1 ST2 ST3 SP_A 10 60 30 ... At x-axis are (should be ...) the species names and at y-axis the frequency per sediment, in stacked bars. I tried to use barplot command but with no results. Could anyone help me on this? Thanks in

Hi, I have a data set with values (L) varying from 1 to 700, with repeated numbers, and I want to sample them according to the probabilities given by a logistic curve P=1/(1+e(-r*(L-Lc))) where r gives "S" the inclination and Lc the "rotation point". P ranges from 0 to 1. As I could see I cannot use this P as prob in sample function. I'd need the probabilities as given by

Thanks for your reply Nassar. What I really want is to overlay (like add=TRUE) the plots 1 and 2. With plots "at the same screen" I meant overlaid and not one beside the other, i.e., only one plot with all the points (1 to 10) in blue (or any other color), the points 5 to 9 in red and a regression line from points 5 to 9. Best regards, Antonio Olinto ----- Original Message -----

Hello, I want to know how do R calculates the number of intervals between tick-marks in the y axis in a plot. I'm making a three y-axes plot and this information would help me a lot. Thanks in advance. Antonio Olinto ---------------------------------------------------------------- Webmail - iBCMG Internet http://www.ibcmg.com.br

Dear list fellows, I want to study time series and use R to analyse time series of fishing data from several species (landings and cpue) investigating the correlation between them and with environmental factors (water temperature, wind, etc.). Searching at Amazon I found three books with examples in R: Time Series Analysis: With Applications in R by Jonathan D. Cryer and Jonathan D. Cryer

Hello all, I have a data frame with year, month, species, fishing gear and catch (Y, M, S, F, C) and I want the sum of C by Y for species "A" and fishing gear "trawl". I tried things like aggregate(C[S=="A" & F=="trawl"], list (Year = Y[S=="A" & F=="trawl"]), fun=sum), but it didn't worked. To overcome this problem I did

Hello R-list members, I’m trying to make a min-avg-max plot (like a boxplot, without box and outliers, i.e., for each class of "x" a vertical line indicating the range (max-min) and an horizontal line or point indicating the mean) with data like: Year Avg Min Max 98 10 7 13 99 12 10 15 01 11 6 14 Which command should be used? Many thanks, Antonio Olinto

Dear R-list members Here goes a question on data frames: I want to create a new data frame excluding some records (rows) from an existing one. Considering the data frame "fish.dat" at the end of this message, I can make a boxplot(Ring~Radius) and identify the points at rows 11 and 25 as outliers. With the command fish.dat[c(11, 25),] I can identify which fishes are related to

Dear R-list members, Some months ago I wrote a message on the usage of gnls (nlme library) and here I come again. Let me give an example: I have a 10 year length-at-age data set of 10 fishes (see growth.dat at the end of this message) and I want to fit a von Bertalanffy growth model, Li= Linf*(1-exp(-k*(ti-t0))) where Li = length at age i, Linf= asymptotic length, k= curvature parameter, ti=

Hi, Some time ago I asked about how to use comma as decimal separator in plots and Mr. Paul Murrell wrote: ------- You could try something with axis() and chartr(), like ... par(mfrow=c(2,1)) plot(1:10/11, rep(1, 10), main="Standard X-Axis") plot(1:10/11, rep(1, 10), main="Customised X-Axis", axes=F) axis(1, at=pretty(1:10/11),

Dear R-list members, Cynthia M. Jones wrote a paper (Fitting growth curves to retrospective size-at-age data, Fisheries Research 46(2000):123-129; abstract at http://www.elsevier.nl/gej-ng/10/19/44/70/24/37/abstract.html)where the SAS procedure MIXED, Macro NLINMIX (Littell et. al., 1996)was used to estimate the von Bertalanffy growth function parameters assuming that data from the same fish are

Hello, About looping, consider the example: for (i in 1:23194) { dat.stat[i,c(2:8)]<-quantile(dat.bat[BL==block[i],2],prob=c(0,0.025,0.25,0.5,0.75,0.975,1)) print(i) } I'd like to have the value of "i" printed for each loop (step). As I could see the values of "i" are shown on screen only after all the work is done. Thanks in advance for any suggestion. Best

Dear R-List members, I want to check if a set of measurements follows better a gamma or a lognormal distribution (see data below). Using shapiro.test I can test for normality (shapiro.test(log (Lt)). To test for gamma (and normal) distribution I would use ks.test but I need to specify its shape and scale. How should I calculate these values in R? I tried > Lt.fit <- glm(Lt ~ 1,

Hi to all, So I'm also a new user. I downloaded the program last week and I think it's great. Thanks to those who have developed R. I have a special interest in GLM as a tool to describe fisheries and its variables and I'm just begging to study it. As I could understand there's two types of GLM sun of squares: in "type I" the factors are added in sequence and