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My question is how to write a periodic function in R. for example if there is a function f(x) that f(x)=f(x+4), for -2<x<2, f(x)=x how to write it in R? thanks a lot! ------------------------------- liyun (Lauren) Ma

Dear listers In R, if I have a sequence x(t), t=1,...N, fft(x) is actually giving us sum(x(t)exp(-i*omega*t)) at fourier frequency omega= 2*pi*i/N, i=0,1,...(N-1). The question is if I want to calculate sum(x(t)exp(-i*2*omega*t)), how can I do it? thanks a lot! ------------------------------- liyun (Lauren) Ma Dept of Statistics North Carolina State University

When I check the size of the plot region usingdev.size("in")a new plot region is produced and in the Rconsole I get[1] 5.333333 5.322917If I mean to produce a plot region with size setting bydev.new(length=3,width=3)a plot region is produced, but the size is [2.281250, 5.322917], as detected by the de.size function. If I type:dev.new(length=10,width=10)I get a plot region of with the

------------------------------------------------------------------From:Duncan Murdoch <murdoch.duncan at gmail.com>Send Time:2018 May 4 (Fri) 17:24To:??? <sunyeping at aliyun.com>; David Winsemius <dwinsemius at comcast.net>Cc:R Help Mailing List <r-help at r-project.org>Subject:Re: [R] why the length and width of a plot region produced by the dev.new() function cannot be correctly set? On?04/05/2018?3:04?AM,?sunyeping?via?R-help?wrote: >? >?-------...

------------------------------------------------------------------From:David Winsemius <dwinsemius at comcast.net>Send Time:2018 May 4 (Fri) 13:25To:??? <sunyeping at aliyun.com>Cc:R Help Mailing List <r-help at r-project.org>Subject:Re: [R] why the length and width of a plot region produced by the dev.new() function cannot be correctly set? >?On?May?3,?2018,?at?6:28?PM,?sunyeping?via?R-help?<r-help at r-project.org>?wrote: >? >?When?I?check?th...