12/2+4 3^2;6^2;2*3^2;(2*3)^2 x<-c(1,2,3,4);y<-c(11,12,13,14);z<-x+y;z;a<-x+2;a 0:12 data2<-letters[1:12];data2 data1<-c(1:12);data1 data3<-data1<6;data3 v1<-c(2,3,5,99) s<-c("aa","bb","cc","dd") b<-c(TRUE,FALSE,TRUE,TRUE) mydata1<-data.frame(Var1=v1,Var2=s,Var3=b) mydata2<-data.frame(v1,s,b) mydata1 a<-c(1,3,5,7) b<-c(1,2,4,8) 5*a a+b u<-c(10,20,30) v<-c(1:7) c(u,v) n<-c(2,3,5);s<-c("aa","bb"); c(n,s) mydata2 x<-1:25;y<-200*x/(x+20) plot(x,y) ?plot M<-matrix(data1, nrow=2, ncol=6, byrow=F);M L1<-list(data1, color="brown", list(letters,1:5));L1 ?women plot(women, xlab = "Height (in)", ylab = "Weight (lb)", main = "women data: American women aged 30-39") women[ ,"height"] women[ ,"weight"] women[3,] names(women) ?lenght() ?length length(diag(4)) # = 16 (4 x 4) length(options()) # 12 or more length(y ~ x1 + x2 + x3) # 3 length(expression(x, {y <- x^2; y+2}, x^y)) # 3 ## from example(warpbreaks) require(stats) fm1 <- lm(breaks ~ wool * tension, data = warpbreaks) length(fm1$call) # 3, lm() and two arguments. length(formula(fm1)) # 3, ~ lhs rhs help(Theoph) ?length weight<-c(60:68) length(weight) weight<-c(60:68) length(weight) weight[weight<67] weight[weight==65] height<-140:148; height; length(height) length(weight); height[weight==65] height[weight>65]; height[weight>70] length(height[weight>65]); length(height[weight>70]); weight[weight<63&weight !=60] MyData<-read.csv(file="covMD.csv", header=TRUE) write.csv(df1, file="NewFile.csv", row.names=FALSE,na=".") ID<-c(1:10) SEXF<-c(1,1,1,1,1,0,0,0,0,0) weight<-c(60,62,64,66,68,70,72,74,76,78) age<-c(35,35,40,40,45,45,50,50,55,55) SCr<-c(seq(0.5,1.4, by=0.1)) CrCL<-round((0.85^SEXF)*weight*((140-age)/(SCr*72)), digits=1) CG.CrCL<-data.frame(ID,SEXF,weight,age,SCr,CrCL) CG.CrCL round(CrCL,0) write.csv(CG.CrCL, file="NEXT.csv", row.names=FALSE, na=".") help(Theoph) df1<-Theoph Theoph[Theoph$Subject==1,] Time=Theoph[ ,"Time"] Time conc=Theoph[ ,"conc"] conc g<-plot(Time,conc) plot ?names() Mydata<-read.csv(file="NEXT.csv",header=FALSE) CG.CrCL time<-c(seq(0, 24, by=0.5)) conc<-c(((800/0.34)^((-0.047/0.34))*time), round(conc,2)) concdata<-data.frame(time,conc) concdata