[R] Case statements in R

[(Ted Harding)]

On 28-Jul-08 17:52:31, Henrik Bengtsson wrote:
> Use '&' for vectors and '&&' for scalars.  Ditto applies to the OR
> operator(s).   /Henrik

What's wrong with using "&" for scalars? Surely it gives the
correct answer? Maybe it's simply a bit slower, or something?

Ted.

> On Mon, Jul 28, 2008 at 10:36 AM, Wade Wall <wade.wall at gmail.com>
> wrote:
>> Hi all,
>>
>> I am trying to convert geometric means in a matrix to cover classes. 
>> My
>> values are as such:
>>
>> perc<-c(0,0.025136418, 0.316227766, 1.414213562,3.16227766,
>> 7.071067812,
>>  15.8113883, 35.35533906, 61.23724357, 84.40971508, 97.46794345)
>> cover<-c(0,1,2,3,4,5,6,7,8,9,10)
>>
>> This is what I am trying to accomplish
>>
>> veg_mean[veg_mean>0 && veg_mean < .1] <- 1
>> veg_mean[veg_mean>= .1 && veg_mean < 1.0] <- 2
>> veg_mean[veg_mean>=1.0  && veg_mean < 2.0] <- 3
>> veg_mean[veg_mean>=2.0  && veg_mean < 5.0] <- 4
>> veg_mean[veg_mean>= 5.0  && veg_mean < 10.0] <- 5
>> veg_mean[veg_mean>= 10.0  && veg_mean < 25] <- 6
>> veg_mean[veg_mean>= 25.0 && veg_mean < 50.0] <- 7
>> veg_mean[veg_mean>=50.0 && veg_mean < 75.0] <- 8
>> veg_mean[veg_mean>= 75.0 && veg_mean < 95.0 ] <- 9
>> veg_mean[veg_mean>= 95.0 && veg_mean <= 100] <- 10
>> veg_mean[veg_mean> 100] <- NA
>>
>> where values are assigned based on the geometric means.  However, I
>> think
>> that my syntax for the && operator is wrong and I can't find a
>> reference to
>> proper syntax.  I basically want to "bin" the geometric means.
>>
>> Any help would be greatly appreciated.
>>
>> Thanks,
>>
>> Wade
>>
>>        [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help at 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-help at 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.

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E-Mail: (Ted Harding) <Ted.Harding at manchester.ac.uk>
Fax-to-email: +44 (0)870 094 0861
Date: 28-Jul-08                                       Time: 19:21:08
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