[R] Any container in R?

Duncan Murdoch murdoch at stats.uwo.ca
Mon Jan 1 18:36:12 CET 2007

On 1/1/2007 11:22 AM, Feng Qiu wrote:
> Hi Duncan:
>          Thanks for your hints.
>          I'm trying to collect distinct elements in one column in a matrix. 
> If there is a map, I can easily build up such a collection. While if using 
> list, I have to check by myself if this element already exists in the 
> collection every time I examine a new entry in the column.

You might want to use the unique() function, or duplicated(), rather 
than doing this yourself.

Duncan Murdoch

> Best,
> Feng
> ----- Original Message ----- 
> From: "Duncan Murdoch" <murdoch at stats.uwo.ca>
> To: "Feng Qiu" <hustqiufeng at sohu.com>
> Cc: <r-help at stat.math.ethz.ch>
> Sent: Monday, January 01, 2007 10:37 AM
> Subject: Re: [R] Any container in R?
>> On 1/1/2007 10:17 AM, Feng Qiu wrote:
>>> R has list and array to contain elements. But does R have more powerful 
>>> container, such as "map" as in C++ STL?  or is there such a package?
>> In what way are maps more powerful than lists?  You can use names to index 
>> lists.
>> The other container in R is the environment; they have fairly strange 
>> semantics, though.
>> Duncan Murdoch

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