Re: [R] "& not meaningful for factors

2008-06-04 Thread Philip Twumasi-Ankrah
It works. Thanks Jim. I guess this will be a "lots of coffee" morning kinda day.

jim holtman <[EMAIL PROTECTED]> wrote: What exactly are you trying to do?  In 
the first case you are making a logical comparison and that is legal for "&".  
In the second you are trying to do a logical operation ("&") between two 
factors and that operation is not defined.  This is what the error message is 
saying.
   
 Also you first attempt is probably missing a comma:
  
  node1  <- data.trt[data.trt$stage=="1B" &  data.trt$diameter=="=< 4", ]



 On Wed, Jun 4, 2008 at 8:10 AM, Philip Twumasi-Ankrah <[EMAIL PROTECTED]> 
wrote:
 I am trying to define groupings from levels of factor variables and this the 
warning message that R give
 
 "& not meaningful for factors".

The nature of my task is this. I have a variable stage which has the levels 
(1B, 2A, 2B) - these are the AJCC TNM stages of cancer, and another variable 
diameter with factor levels ("=< 4", "4 - 6.5, > 6.5; limit values are 
exclusive).
 
I am trying to define series of groupings based on these variables and others 
like them.

My first attempts were;

1. node1  <- data.trt[data.trt$stage=="1B" &  data.trt$diameter=="=< 4"]
 2.  data.trt$stage[data.trt$stage=="1B"]& 
data.trt$diameter[data.trt$diameter=="=< 4"]

The second attempt was purely a fishing exercise.

R gave me the waring message:

Warning message:
 In Ops.factor(data.trt$stage[data.trt$stage == "1B"], 
data.trt$diameter[data.trt$diameter ==  :
 & not meaningful for factors


My question is how do I get round this and by implication is there an 
alternative way of defining a logical operation applicable to factors.
 
Thanks already for the help.

Philip


A Smile costs Nothing

But Rewards Everything

Happiness is not perfected until it is shared
 -Jane Porter
 


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-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem you are trying to solve?  


A Smile costs Nothing  

 But Rewards Everything

Happiness is not perfected until it is shared
  -Jane Porter  
  


   
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Re: [R] "& not meaningful for factors

2008-06-04 Thread jim holtman
What exactly are you trying to do?  In the first case you are making a
logical comparison and that is legal for "&".  In the second you are trying
to do a logical operation ("&") between two factors and that operation is
not defined.  This is what the error message is saying.

Also you first attempt is probably missing a comma:

 node1  <- data.trt[data.trt$stage=="1B" &  data.trt$diameter=="=< 4", ]


On Wed, Jun 4, 2008 at 8:10 AM, Philip Twumasi-Ankrah <
[EMAIL PROTECTED]> wrote:

> I am trying to define groupings from levels of factor variables and this
> the warning message that R give
>
>  "& not meaningful for factors".
>
> The nature of my task is this. I have a variable stage which has the levels
> (1B, 2A, 2B) - these are the AJCC TNM stages of cancer, and another variable
> diameter with factor levels ("=< 4", "4 - 6.5, > 6.5; limit values are
> exclusive).
>
> I am trying to define series of groupings based on these variables and
> others like them.
>
> My first attempts were;
>
> 1. node1  <- data.trt[data.trt$stage=="1B" &  data.trt$diameter=="=< 4"]
> 2.  data.trt$stage[data.trt$stage=="1B"]&
> data.trt$diameter[data.trt$diameter=="=< 4"]
>
> The second attempt was purely a fishing exercise.
>
> R gave me the waring message:
>
> Warning message:
> In Ops.factor(data.trt$stage[data.trt$stage == "1B"],
> data.trt$diameter[data.trt$diameter ==  :
>  & not meaningful for factors
>
>
> My question is how do I get round this and by implication is there an
> alternative way of defining a logical operation applicable to factors.
>
> Thanks already for the help.
>
> Philip
>
>
> A Smile costs Nothing
>
> But Rewards Everything
>
> Happiness is not perfected until it is shared
>  -Jane Porter
>
>
>
>[[alternative HTML version deleted]]
>
> __
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>



-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem you are trying to solve?

[[alternative HTML version deleted]]

__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.


[R] "& not meaningful for factors"

2008-06-04 Thread Philip Twumasi-Ankrah
I am trying to define groupings from levels of factor variables and this the 
warning message that R give 

 "& not meaningful for factors".

The nature of my task is this. I have a variable stage which has the levels 
(1B, 2A, 2B) - these are the AJCC TNM stages of cancer, and another variable 
diameter with factor levels ("=< 4", "4 - 6.5, > 6.5; limit values are 
exclusive). 

I am trying to define series of groupings based on these variables and others 
like them. 

My first attempts were;

1. node1  <- data.trt[data.trt$stage=="1B" &  data.trt$diameter=="=< 4"] 
2.  data.trt$stage[data.trt$stage=="1B"]& 
data.trt$diameter[data.trt$diameter=="=< 4"]

The second attempt was purely a fishing exercise.

R gave me the waring message:

Warning message:
In Ops.factor(data.trt$stage[data.trt$stage == "1B"], 
data.trt$diameter[data.trt$diameter ==  :
  & not meaningful for factors


My question is how do I get round this and by implication is there an 
alternative way of defining a logical operation applicable to factors.

Thanks already for the help.

Philip


A Smile costs Nothing  

 But Rewards Everything

Happiness is not perfected until it is shared
  -Jane Porter  
  


   
[[alternative HTML version deleted]]

__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.