[R] Using apply for two datasets

[Gang Chen]

Thanks a lot for the suggestions, Jorge and Satoshi Takahama! Both
approaches work well...

Gang

On Tue, Jan 6, 2009 at 2:12 PM, Satoshi Takahama <s.takahama at yahoo.com> wrote:
> Perhaps you can convert your matrices to data frames as in:
>
> mapply(t.test,as.data.frame(myData1),as.data.frame(myData2))
> to test by column and
>
> mapply(t.test,as.data.frame(t(myData1)),as.data.frame(t(myData2)))
>
>
> to test by row?
>
>
> ----- Original Message ----
> From: Gang Chen <gangchen6 at gmail.com>
> To: Henrique Dallazuanna <wwwhsd at gmail.com>
> Cc: r-help at stat.math.ethz.ch
> Sent: Tuesday, January 6, 2009 10:10:44 AM
> Subject: Re: [R] Using apply for two datasets
>
> Thanks a lot for the quick help!
>
> mapply() seems promising. However, mapply(t.test, myData1, myData2)
> would not work, so how can I specify the margin in mapply() which
> function t.test() will be applied over? For example, I specify the 2nd
> dimension (column) in apply(myData1, 2, t.test) to run one-sample
> t-test. Is there a way I can achieve the same with mapply()?
>
> Thanks again,
> Gang
>
>
> On Tue, Jan 6, 2009 at 12:34 PM, Henrique Dallazuanna <wwwhsd at gmail.com> wrote:
>> I think that you can use mapply for this.
>>
>> On Tue, Jan 6, 2009 at 3:24 PM, Gang Chen <gangchen6 at gmail.com> wrote:
>>>
>>> I can run one-sample t-test on an array, for example a matrix myData1,
>>> with the following
>>>
>>> apply(myData1, 2, t.test)
>>>
>>> Is there a similar fashion using apply() or something else to run
>>> 2-sample t-test with datasets from two groups, myData1 and myData2,
>>> without looping?
>>>
>>> TIA,
>>> Gang