R help - Feb 2006 - problem with simple if() statement

the following code apprantely, for some grand old reason, induces a syntax
error:
  
  if (seq[i] = "A") m <- trans[1,]
  
  where seq is a vector and trans is a matrix. I cannot for the life of me see
why this is wrong. Syntax error is:
  
  Error: syntax error in "if (seq[i] ="
  
  Sincerely,
  
  Norman Goodacre
  
  
		
---------------------------------

---------------------------------
  
	[[alternative HTML version deleted]]

Norman Goodacre wrote:
> the following code apprantely, for some grand old reason, induces a syntax
error:
>   
>   if (seq[i] = "A") m <- trans[1,]
>   
>   where seq is a vector and trans is a matrix. I cannot for the life of me
see why this is wrong. Syntax error is:
>   
>   Error: syntax error in "if (seq[i] ="
I guess you mean "==" ....

Uwe Ligges

>   
>   Sincerely,
>   
>   Norman Goodacre
>   
>   
> 		
> ---------------------------------
> 
> ---------------------------------
>   
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html

Em Seg 06 Fev 2006 04:22, Norman Goodacre escreveu:
>   if (seq[i] = "A") m <- trans[1,]
I'll guess that it is the use you are making of the name 'seq'. :-)
'seq' is an R function. Try some other name.


-- 

          Alexandre

Norman Goodacre wrote:
> the following code apprantely, for some grand old reason, induces a syntax
error:
>   
>   if (seq[i] = "A") m <- trans[1,]
>   
>   where seq is a vector and trans is a matrix. I cannot for the life of me
see why this is wrong. Syntax error is:
>   
>   Error: syntax error in "if (seq[i] ="
>   
>   Sincerely,
>   
>   Norman Goodacre
Please, read "An Introduction to R" provided with any version of R.
The
correct syntax for an equality condition is "==", not "=",
so:

 > if (seq[i] == "A") ....

Best,

Philippe Grosjean

Norman, 
you probably want:
 
  if (seq[i] == "A") m <- trans[1,]
  
hth,
Colin
>>> Norman Goodacre <taranpen at yahoo.co.uk> 06/02/2006 06:22
>>>
the following code apprantely, for some grand old reason, induces a
syntax error:
  
  if (seq[i] = "A") m <- trans[1,]
  
  where seq is a vector and trans is a matrix. I cannot for the life of
me see why this is wrong. Syntax error is: 
  
  Error: syntax error in "if (seq[i] ="
  
  Sincerely,
  
  Norman Goodacre
  
  
		
---------------------------------

---------------------------------
  
	[[alternative HTML version deleted]]

______________________________________________
R-help at stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help 
PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html

Hi Norman !
 
I observe that R syntax is very close to C/C++ or Java

--- Philippe Grosjean <phgrosjean at sciviews.org> a
??crit??:
> Norman Goodacre wrote:
> > the following code apprantely, for some grand old
> reason, induces a syntax error:
> >   
> >   if (seq[i] = "A") m <- trans[1,]
> >   
> >   where seq is a vector and trans is a matrix. I
> cannot for the life of me see why this is wrong.
> Syntax error is: 
> >   
> >   Error: syntax error in "if (seq[i] ="
> >   
> >   Sincerely,
> >   
> >   Norman Goodacre
> 
> Please, read "An Introduction to R" provided with
> any version of R. The 
> correct syntax for an equality condition is "==",
> not "=", so:
> 
>  > if (seq[i] == "A") ....
> 
> Best,
> 
> Philippe Grosjean
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
> http://www.R-project.org/posting-guide.html
>

Evidently, my R has some feature of error messages disabled.
>>>>> "NG" == Norman Goodacre <taranpen at
yahoo.co.uk> writes:
NG> the following code apprantely, for some grand old reason, induces a
syntax error:
NG>   if (seq[i] = "A") m <- trans[1,]

NG>   Error: syntax error in "if (seq[i] ="

Where Norman gets this nice error message pointing to the exact
location of the error, all I get is:
> if (1=1) 5
Error: syntax error
>
How do I turn on more-verbose error messages? Is this an environmental
issue, or a build issue?

This is a debian (ubuntu breezy) build; happens even when I run R --vanilla

R.version
         _                
platform i486-pc-linux-gnu
arch     i486             
os       linux-gnu        
system   i486, linux-gnu  
status                    
major    2                
minor    1.1              
year     2005             
month    06               
day      20               
language R                

TIA!

-- 
Patricia J. Hawkins
Hawkins Internet Applications
www.hawkinsia.com