R version 4.5.2 (2025-10-31 ucrt) -- "[Not] Part in a Rumble"
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Platform: x86_64-w64-mingw32/x64

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> 1+2
[1] 3
> 2+3
[1] 5
> plot(1:10)
> 10+20
[1] 30
> 20+30
[1] 50
> 30-40
[1] -10
> 
> 
> #now altogether
> 10+20
[1] 30
> 20+30
[1] 50
> 30-40
[1] -10
> q()
> i <- 0; while(1>0) i<-i+1 

> i
[1] 566607821


> > > 
> 
> 
> x <- 1+2
> x
[1] 3
> y = 2+3 
> y
[1] 5
> 5+6 -> z 
> z
[1] 11
> X^2
Error: object 'X' not found
> x^2
[1] 9
> for <- 4
Error: unexpected assignment in "for <-"
> 
> 
> m <- mean(rivers)
> m
[1] 591.1844
> rivers   #built-in dataset
  [1]  735  320  325  392  524  450 1459  135  465  600  330  336  280  315  870
 [16]  906  202  329  290 1000  600  505 1450  840 1243  890  350  407  286  280
 [31]  525  720  390  250  327  230  265  850  210  630  260  230  360  730  600
 [46]  306  390  420  291  710  340  217  281  352  259  250  470  680  570  350
 [61]  300  560  900  625  332 2348 1171 3710 2315 2533  780  280  410  460  260
 [76]  255  431  350  760  618  338  981 1306  500  696  605  250  411 1054  735
 [91]  233  435  490  310  460  383  375 1270  545  445 1885  380  300  380  377
[106]  425  276  210  800  420  350  360  538 1100 1205  314  237  610  360  540
[121] 1038  424  310  300  444  301  268  620  215  652  900  525  246  360  529
[136]  500  720  270  430  671 1770
> var(rivers)
[1] 243908.4
> ls()
[1] "i" "m" "x" "y" "z"
> history()
> z <- 10; z <- z^2; #z <- z-10
> z
[1] 100
> #w <- (3+5)^2    #this is what i wanted to type
> w <- (3+5)^
+ 2
> w
[1] 64
> w <- (3+5)^
+ 2/(3+4)^2 
> w
[1] 1.306122
> getwd()
[1] "C:/Users/user/Documents"
> ls()
[1] "i" "m" "w" "x" "y" "z"
> save.image('my1session.RData') 
> getwd
function () 
.Internal(getwd())
<bytecode: 0x000002765fd18e78>
<environment: namespace:base>
> 
> 
> setwd('C:/Users/user/Documents/course1')
> save.image('my2session.RData') 
> setwd('C:/Users/user/Documents/course2')
> save.image('my3session.RData')