R help - Aug 2006 - Question on .Options$max.print

Hi,


I have a tiny question concerning .Options$max.print


I have to set up this value to a greater value than 10000 because I  
want to concatenate my output of a function to one single string (for  
connivence).

I did this via .Options$max.print <- 64000 or options(max.print=64000)

Then I call out <- paste(out, blabla) several times, but nchar(out)  
is never larger than 10000.

I read in the help about '.Options' that this is not yet used in base  
R. Could this be my problem?


Thanks for any hint

Hans

BTW I believe, there is a typo within the help page about '.Options'

...
The ?factory-fresh? default settings of some of these options are
...
max.print     1000
...


This should be
...
max.print     10000
...

>>>>> "HansJB" == Hans-Joerg Bibiko <bibiko at
eva.mpg.de>
>>>>>     on Mon, 14 Aug 2006 17:56:30 +0200 writes:
    HansJB> Hi, I have a tiny question concerning
    HansJB> .Options$max.print


    HansJB> I have to set up this value to a greater value than
    HansJB> 10000 because I want to concatenate my output of a
    HansJB> function to one single string (for connivence).

    HansJB> I did this via .Options$max.print <- 64000 or
    HansJB> options(max.print=64000)

    HansJB> Then I call out <- paste(out, blabla) several times,
    HansJB> but nchar(out) is never larger than 10000.

    HansJB> I read in the help about '.Options' that this is not
    HansJB> yet used in base R. Could this be my problem?

well, it at least makes clear that your assumption that 
this option would influence your paste() must be wrong.

I don't think there's any option influencing paste()
and I hope there won't every be any.
Options typically should only influence ``output formatting''
but not the result of a ``computational'' (i.e. non-printing/plotting)
function.

    HansJB> Thanks for any hint

The posting guide -- and every footer of all R-help posting asks
for a small reproducible example of R code.
So please do provide one
[and, BTW, keep this thread on R-help; do not reply privately..]

    HansJB> Hans

    HansJB> BTW I believe, there is a typo within the help page
    HansJB> about '.Options'

    HansJB> ...  The ?factory-fresh? default settings of some
    HansJB> of these options are ...  max.print 1000 ...


    HansJB> This should be ...  max.print 10000 ...

Yes, thank you.

Martin Maechler, ETH Zurich

Dear list members,

sorry for my incompleteness!



My problem is the following:
(R 2.3.1 on Mac OS X 10.4.7 RAM 1GByte using Mac GUI)

I have a function like this:

foo1 <- function()
{
	out <- NULL
	for(i in 1:10010) out <- paste(out, i, ". line\n",
sep="")
	return(out)	
}
a <- foo1()

Now I want to display 'a' on the screen:

cat(a)

This doesn't work. 'a' is displayed only until '830. line'

print(a)

The same, 'a' is displayed only until '\n754. line\n755'.

cat(a, file='test.txt') # OK
works fine. That means, internally 'a' is fine.


Then I tried this way:

foo2 <- function()
{
	out <- NULL
	for(i in 1:10010) out <- c(out, paste(i, ". line",
sep=""))
	return(out)	
}
a <- foo2()

With

cat(a,sep="\n")
I see the complete content of 'a'.

paste(a, collapse = "\n")
I only see 'a' until '\n754. line\n755'.

cat(paste(a, collapse ="\n"))
I only see 'a' until '830. line'.

cat(paste(a, collapse ="\n"),file='test.txt')
This is OK.


My question now is whether there is an option to specifiy the maximum  
size of a string which is displayed on the screen (running R in a  
GUI)? Or is this fixed?

I read the help page about '.Options' and I found a variable  
'max.print' with the comment that is not yet used in basic R.
I don't know whether this variable is responsible for that. I  
increased 'max.print' but nothing changed.

##########
If I try this code on a Windows XP machine with 756 MByte RAM R-GUI  
says after executing

foo1 <- function()
{
	out <- NULL
	for(i in 1:10010) out <- paste(out, i, ". line\n",
sep="")
	return(out)	
}
a <- foo1()
cat(a)

...
7548. lineWarning message:
printing of extremely long output is truncated

At least Windows writes a warning message.

###########
If I start a R session without the R-GUI via Mac Terminal typing 'R'

a<-foo1()
cat(a)

everything works perfectly!!!


I know the issue of outputting long strings and the way to display  
long strings via foo2() would be ok for me, but I spent some time to  
figure out why my function foo1() didn't work. R, running in GUI on  
Mac, don't give you a warning. Now I know that if I print a long  
string at the Mac-GUI-console the missing final quote character is an  
indicator for a truncated output on a Mac. Maybe it would be nice to  
output a warning(?)

Cheers,

Hans

Dear all,


My question is concerned to the kind how a function is called.

Example A:

 > foo(1)

Example B:

 > a <- foo(1)


Is there any way for the function foo() to recognise whether the  
returned value of foo() is stored in a variable or not, i.e. to  
distinguish between Example A and B?


Any comments are welcomed.

Many thanks in advance

Hans