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...uot;) pdf(filename,width=6.5,height=4.5) plot(lat ~ long, data = quakes) graphics.off() } # I can open the pdf files. Hope you can help me. Thanks so much, --- Jian Zhang Department of Renewable Resources University of Alberta Edmonton, Alberta T6G 2H1, Canada Phone (office): 780-492-8670 Email: jzhang1982@gmail.com; zjian@ualberta.ca [[alternative HTML version deleted]]

I have some programs which were writen in mathematica or c language, but I donot know how to use these software. So I want to run them in R. Can I do it ? How to run "mathematica" or "c" programs in R? Jian Zhang [[alternative HTML version deleted]]

I want to get the data in a circle from a large square plot. If the data includes only two columns or more columns which is number style, I can do it. But if the data includes other columns which is not number style (e.g. species name), I donot know how to do it. And I donot want to delete the columns because it is useful to me. e.g. species x y a 12

I can load the package in other R file, but I can not do it in the file. How to solve the question? > local({pkg <- select.list(sort(.packages(all.available = TRUE))) + if(nchar(pkg)) library(pkg, character.only=TRUE)}) Loading required package: tcltk Loading required package: car Error in parse(file, n, text, prompt) : syntax error in "*" Error: .onAttach failed in

I want to transform the data by "tapply" to one dataframe. But I can not get it. For example: > tst=tapply(point,pp,length) > tst[1:10] p1 p10 p100 p1000 p1001 p1002 p1003 p1004 p1005 p1006 1 5 1 8 6 5 8 7 4 4 > res=as.data.frame(tst) # I try to transform it > res[1:10,] p1 p10 p100 p1000 p1001 p1002 p1003 p1004 p1005 p1006 1 5 1 8 6 5

Hi. I want to get a series data just like this: sp1 sp2 1 2 1 3 1 4 1 5 2 3 2 4 2 5 3 4 3 5 4 5 I can get one part of the data every time, but I can get the data directly. I try to use the loop, but it can not work. How to get it ? Thanks. pair.fn=function(i,sp=5){res=data.frame(sp1=rep(i,(sp-i)),sp2=(i+1):sp) return(res)} pair.fn(1) pair.fn(2) ..... [[alternative HTML

Hi! I want to choose part of the data. But it has a question. > attach(PIKO) > PIKO[1:5,] code species dbh x y tag status branch 92 10142 PIKO 38.9 6.05 12.81 10165 alive 0 109 10213 PIKO 41.0 6.71 26.21 10202 alive 0 135 10222 PIKO 48.3 18.98 21.28 10214 alive 0 146 10223 PIKO 47.0 19.45 22.83 10224 alive 0 147 10223 PIKO 20.0 19.74

If I do not add "ress" into the data frame "res", there is no quote in the data frame. However, I add "ress", all column were found the quote. How to remove it? If you can delete the quote in the file "ress", that is better. Thanks. > ress[1:10] [1] "ABHO.ABNE" "ABHO.ACBA" "ABHO.ACGI" "ABHO.ACKO"

I think there is a question in R. I donot know the reason. This is my data about comulative percentage figure. The result is not right. The first point (no=1,leiji=26.94350) in the plot figure was showen in a lower location. Why? Thanks ! > fre no leiji 1 1 26.94350 2 2 46.86401 3 3 60.59032 4 4 72.17355 5 5 77.85521 6 6 82.05853 7 7 85.56495 8 8 87.64378 9 9

I want to gain thousands of random sampling data by randomizing the presence-absence data. Meantime, one important limition is that the row and column sums must be fixed. For example, the data "tst" is following: site1 site2 site3 site4 site5 site6 site7 site8 1 0 0 0 1 1 0 0 0 1 1 1 0 1 0 1 1 0 0 0 1 0 1 0 0 0 0 1 0 1 0 1 1 0 1 0 0 0 0 0 0 1 0 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 1 0 1 0

Hi,everyone. I use the following program calculates Fisher's alpha from counts of individuals and species. The program is wrote by Prof. Kyle Harm. However, when I run the program, it can work very quickly sometimes, but it can not work very well sometimes. It depends on the counts of individuals and species. For example, > calc.alpha(1000,70) [1] 17.14375 > calc.alpha(10000,70) [1]

I want to load many files in the R. The names of the files are "Sim1.txt", " Sim2.txt", "Sim3.txt", "Sim4.txt", "Sim5.txt" and so on. Can I read them at one time? What should I do? I can give the same names in R. Thanks. For example: > tst=paste("Sim",1:20,".txt",sep="") # the file names > tst [1]

I want to analyze the co-occurrence of some species. In some papers, the authors said that the index"the number of species combinations (COMBO)" is a good index. I try to calculate the index by R language. But I can not get the right value. I think that I do not understand the concept of the index because my english is not good. The concept: *The number of species combinations *This

I did the contour map by "filled contour" and I want to add some points in this map. But It cannot be added truely because the bar is in the right. I want to know how to delete the bar in the right or add the points in the contour map. Thanks! [[alternative HTML version deleted]]

Hello. I want to draw the contour map by package "CTFs". But: Error in plot.new() : plot region too large # the plot area is 1000 * 500. How to solve this trouble? Thanks! Jian zhang [[alternative HTML version deleted]]

I want to replace some objects in one row or column.For example, One colume: a,b,a,c,b,b,a,a,c. I want to replace "a" with "1", "b" with "2", and "c" with "3". Like this: 1,2,1,3,2,2,1,1,3. How to do it? I donot know how to do it. Thanks. [[alternative HTML version deleted]]

I find one row in my large dataset. But when I use the "rownames" for the data on the 100,000 row, the result show nothing. I try it by the following example, it still likes that. > tst[rownames(tst)==100000,] [1] x y <0 rows> (or 0-length row.names) ############## > tst=data.frame(x=1:200000,y=200000:1) > tst[rownames(tst)==1,] x y 1 1 200000 >

I want to add the legend for my figure using "auto.key" in the xyplot function (library(lattice)). But I don't know how to change the colors of the lines in the "legend" part. I tried to add "col=1:8" in the "auto.key", but it changes the colors of the text of my Legend, not the lines. How can I change the colors of the lines?

I have a dataset like this: sites years Var1 Var2 1 1960 505 3.013833 1 1961 533 4.118784 1 1962 609 14.96386 1 1963 465 -3.74409 1 1964 837 41.70164 1 1965 727 29.53478 2 1960 493 3.269235 2 1961 535 5.386015 2 1962 608 16.26244 2 1963 469 -2.09736 2 1964 830 42.01942 2 1965 715 29.92867 3 1960 489

Now I have the forest plot data with x, y locations, and I measured the DBH for every indivicuals. The data looks like that: x=runif(100,0,100) y=runif(100,0,100) dbh=runif(100,1,100) rdata=data.frame(x,y,dbh) > rdata[1:5,] x y dbh 1 99.5354145 1.412844 34.10112 2 0.8259361 87.737036 39.12914 3 6.5678613 65.699032 22.55990 4 67.2987881 72.053877 45.83978 5 2.2491372