The Art of R Programming

As another example, consider our tablecttabin the examples in the pre- ceding sections: > tabdom(cttab,2) Vote.for.X Voted.Fo ...

The sorting approach in line 7, which makes use oforder(), is the stan- dard way to sort a data frame (worth remembering, since ...

where the bins are defined to be the semi-open intervals(b[1],b[2]], (b[2],b[3]],.... Here’s an example: z [1] 0.88114802 0.285 ...

...

7 R PROGRAMMING STRUCTURES R is a block-structured language in the man- ner of the ALGOL-descendant family, such as C, C++, Pyth ...

7.1.1 Loops.......................................................... In Section 1.3, we defined theoddcount()function. In that ...

This code shows three different ways of accomplishing the same thing, withbreakplaying a key role in the second and third ways. ...

14 print(commdata$countabsamecomm/nreps) 15 } Because this simple example has just two levels, it’s not too bad. How- ever, nest ...

Let’s look at an example of usingget(). Say we have two matrices,uand v, containing statistical data, and we wish to apply R’s l ...

} else { x<-3 y<-4 } It looks simple, but there is an important subtlety here. Theifsection consists of just a single stat ...

7.2 Arithmetic and Boolean Operators and Values................................ Table 7-1 lists the basic operators. Table 7-1:B ...

The Boolean valuesTRUEandFALSEcan be abbreviated asTandF (both must be capitalized). These values change to 1 and 0 in arithmeti ...

The second formal argument is namedheader. The= FALSEfield means that this argument is optional, and if we don’t specify it, the ...

for (n in x) { if(n%%2==1)k<-k+1 } } It wouldn’t work, for a rather subtle reason: The last executed statement here is the ca ...

> g() function(x) return(x^2) <environment: 0x8aafbc0> If your function has multiple return values, place them in a lis ...

This is handy if you’re using a function that you wrote but which you’ve forgotten the details of. Printing out a function is al ...

> f(3,2) [1] 1 > g <- function(h,a,b) h(a,b) > g(f1,3,2) [1] 5 > g(f2,3,2) [1] 1 And since functions are objects, ...

7.6.1 The Top-Level Environment....................................... Consider this example: >w<-12 > f <- function ...

possible—and sometimes desirable from the point of view of the encapsu- lation goal of object-oriented programming—to define a f ...

Environments created by inheritance in this manner are generally referred to by their memory locations. Here is what happened af ...