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The following caught me off-guard: R> z <- 1i + 1:10 R> z <- Re(z) R> z [1] 1 2 3 4 5 6 7 8 9 10 as expected. But look: R> z <- 1i + 1:10 R> make.real <- abs(z) < 1000 R> z[make.real] <- Re(z[make.real]) R> z [1] 1+0i 2+0i 3+0i 4+0i 5+0i 6+0i 7+0i 8+0i 9+0i 10+0i R> didn't make z a real vector, which is what I wanted. ?"[<-" says If one of these expressions appears on the left side of an assignment then that part of 'x' is set to the value of the right han...

Hi, I am going to be attempting a build of R for the alphas (our main need is to collate and present graphically, performance metrics we gather on our applications). We have: CC=cc, CXX=cxx, Fortran V5.51 (f77, f95), GNU make 3.80, Perl 5.8.4 I am hesitant to rebuild GCC on this platform, and would like to know if others have success in building R with native C, C++ and Fortran. I plan on

...forge.r-project.org/projects/expm/ > >But that matrix is not negative definite! It has 2 positive and one >negative eigenvalue. It is non-positive definite. > >It is fairly easy in any case to get a matrix square root from the eigen >decomposition: > > > v%*%diag(sqrt(d+0i))%*%t(v) > [,1] [,2] [,3] >[1,] 0.5164499+0.4152591i -0.1247682-0.0562317i -0.7257079+0.3051868i >[2,] -0.1247682-0.0562317i 0.9618445+0.0076145i 0.3469916-0.0413264i >[3,] -0.7257079+0.3051868i 0.3469916-0.0413264i 1.0513849+...

...version of qr.coef, with the two lines in question changed as above (and no other modifications). Examples: > A <- matrix(rnorm(9),3,3) > B <- matrix(rnorm(9),3,3) > solve(A+1i*B,A+1i*B) [,1] [,2] [,3] [1,] 1.000000e+00+0.000000e+00i -1.853360e-17-1.199306e-17i 0+0i [2,] 2.338819e-17-1.192988e-19i 1.000000e+00+1.155338e-20i 0+0i [3,] -6.940188e-18+1.120842e-17i 5.188659e-17-3.226848e-17i 1+0i > qr.solve(A+1i*B,A+1i*B) [,1] [,2] [1,] 1.000000e-00-2.583088e-16i 1.000000e-...

Hello Does anybody know how one can compute d largest eigenvalues/eigenvectors in R, like in MATLAB eigs function ? eigen function computes all eigenvectors/eigenvalues, and they are slightly different than those generated by matlab eigs. Thanks in advance -- View this message in context: http://www.nabble.com/matlab-eigs-function-in-R-tp17619641p17619641.html Sent from the R help mailing list

...51). I have had some difficulty using the polyroot() function. For example, in Win 98, R 1.1.1, > polyroot(c(2,1,1)) correctly (per the help index) gives the roots of 1 + (1*x) + (2*x^2) as [1] -0.5+1.322876i -0.5-1.322876i However, > polyroot(c(-100,0,1)) gives the roots of [1] 10+0i -10+0i which corresponds to -100 + x^2, not 1 - (100*x^2). Also, > polyroot(c(0,0,0,1)) gives [1] 0+0i 0+0i -10+0i which aren't all roots of x^3. Thanks for all your efforts. I apologize if I'm missing something. Kristian Markon -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-....

...s of a complex number be printed to the same precision? The imaginary part of 0 looks a bit odd when log10(real/imag) >=~ getOption("digits"), but I'm not sure it is awful. Some people might expect the same number of significant digits in the two parts. > 1e7+4i [1] 10000000+0i > 1e7+5i [1] 10000000+0i > 1e10 + 1000i [1] 1e+10+0e+00i > getOption("digits") [1] 7 > options(digits=4) > 1e4+4i [1] 10000+0i > 1e7+1000i [1] 10000000+0i > version _ platform i386-pc-mingw32 arch i386 os mingw32 system...

...is-behaviour of the function 'eigen' in 'base', for the following input matrix: A <- matrix(c(2,3,4,-1,3,1,1,-2,0),3,3) eigen(A) I obtain the following results, which are incorrect for eigenvalues and eigenvectors 2 and 3 (incorrect imaginary portions): $values [1] 3+0.000000e+00i 1+1.869518e-08i 1-1.869518e-08i $vectors [,1] [,2] [,3] [1,] -0.5345225+0i 4.720910e-17+2.643897e-09i 4.720910e-17-2.643897e-09i [2,] -0.2672612+0i 7.071068e-01+0.000000e+00i 7.071068e-01+0.000000e+00i [3,] -0.8017837+0i 7.071068e-01-2.6438...

...t matrix is not negative definite! It has 2 positive and one >>> negative eigenvalue. It is non-positive definite. >>> >>> It is fairly easy in any case to get a matrix square root from the eigen >>> decomposition: >>> >>>> v%*%diag(sqrt(d+0i))%*%t(v) >>> [,1] [,2] [,3] >>> [1,] 0.5164499+0.4152591i -0.1247682-0.0562317i -0.7257079+0.3051868i >>> [2,] -0.1247682-0.0562317i 0.9618445+0.0076145i 0.3469916-0.0413264i >>> [3,] -0.7257079+0.3051868...

Dear all, We seem to have found a "strange" behaviour in the hyperbolic tangent function tanh on Windows. When running tanh(356 + 0i) the Windows result is NaN + 0.i while on Mac the result is 1 + 0i. It doesn't seem to be a floating point error because on Mac it is possible to run arbitrarily large numbers (say tanh( 999999677873648767519238192348124812341234182374817239847812738481234871823+0i) ) and still get 1 + 0i as re...

...old versions of the GNU C standard library; this seems relevant. The discussion by Martin Maechler suggest "using R's internal substitute". So how do I enable this? Or does this requires updating the C standard library? ** From complex.Rout.fail > stopifnot(identical(tanh(356+0i), 1+0i)) Error: identical(tanh(356 + (0+0i)), 1 + (0+0i)) is not TRUE In addition: Warning message: In tanh(356 + (0+0i)) : NaNs produced in function "tanh" Execution halted Best, Kasper [[alternative HTML version deleted]]

Hi the following gave me a shock: > atan(2) [1] 1.107149 > atan(2+0i) [1] -0.4636476+0i > or, perhaps more of a gotcha: > atan(1.0001+0i) [1] -0.7853482+0i > atan(0.9999+0i) [1] 0.7853482+0i > evidently atan()'s branch cuts aren't where I thought they were. Where do I look for documentation on this? -- Robin Hankin Uncertainty Analys...

...1.143118e-04 1.428898e-04 [6] 1.714678e-04 2.000457e-04 2.286237e-04 2.572016e-04 2.857796e-04 I would like to do an inverse fft using these frequencies so that I can recreate the interpolated time series. But when I do: >fft(fft(ts_lomb))/length(ts_lomb) I get: ... [17485] 0.00037151349-0i 0.00034293553-0i 0.00031435757-0i 0.00028577961-0i [17489] 0.00025720165-0i 0.00022862369-0i 0.00020004572-0i 0.00017146776-0i [17493] 0.00014288980+0i 0.00011431184-0i 0.00008573388-0i 0.00005715592-0i My question: 1) The numbers don't make sense to me. Shouldn't I have both cosine and...

...ulation. My problem is that I want to have the 95% confidence interval of the specific lambda (1.056 in the case). Is there a way to do that? Are the other eigen value shown in the output could help me doing it. I would very appreciate any help. Thanks for your time $values [1] 1.0561867+0.0000000i 0.0749653+0.5249157i 0.0749653-0.5249157i [4] 0.4498348+0.0795373i 0.4498348-0.0795373i -0.3357868+0.0000000i $vectors [1,] -0.72849129+0i -0.11058308+0.3293511i -0.11058308-0.3293511i 0.00244042+0.03012017i 0.00244042-0.03012017i [2,] -0.41384232+0i 0.35124594+0.1765638i 0.35124594-0.1765638i 0.01...

...te: jj <- matrix(0,100,100) A <- exp(-0.1*(row(jj)-col(jj))^2) A's being positive-definite is important to me: > min(eigen(A,T,T)$values) [1] 2.521153e-10 > Coercing A to a complex matrix should make no difference, but makes eigen() return the wrong answer: > min(eigen(A+0i,T,T)$values) [1] -0.359347 > This is very, very wrong. I would expect these two commands to return identical values, up to numerical precision. Compare svd(): > dput(min(eigen(A,T,T)$values)) 2.52115250343783e-10 > dput(min(eigen(A+0i,T,T)$values)) -0.359346984206908 > dput(min(sv...

...is seems relevant. The discussion by Martin Maechler suggest "using R's >> internal substitute". So how do I enable this? Or does this requires >> updating the C standard library? >> >> ** From complex.Rout.fail >> >> stopifnot(identical(tanh(356+0i), 1+0i)) >>> >> Error: identical(tanh(356 + (0+0i)), 1 + (0+0i)) is not TRUE >> In addition: Warning message: >> In tanh(356 + (0+0i)) : NaNs produced in function "tanh" >> Execution halted >> >> Best, >> Kasper >> >>...

...[], 8) = 0 [pid 16929] rt_sigprocmask(SIG_BLOCK, [HUP INT USR1 USR2 ALRM CHLD IO], [], 8) = 0 [pid 16929] writev(3, [{"\232\0\0\0\n\1\0\0\0\0\0\0*\0\1\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 64}, {"E\0v\0e\0r\0e\0s\0t\0 \0D\0i\0c\0t\0i\0o\0n\0a\0r\0y\0 \0S\0e\0t\0u\0p\0 \0i\0s\0 \0p\0r\0e\0p\0a\0r\0i\0n\0g\0 \0t\0h\0e\0 \0I\0n\0s\0t\0a\0l\0l\0S\0h\0i\0e\0l\0d\0 \0W\0i\0z\0a\0r\0d\0,\0 \0w\0h\0i\0c\0h\0 \0w\0i\0l\0l\0 \0g\0u\0i\0d\0e\0 \0y\0o\0u\0 \0t\0h\0r\0o\0u\0g\0h\0 \0t\0h\0e\0 \0p\0r\0o\0g\0r\0a\0m\0 \0s\0e\0t\0u\0p...

The following command, temp <- read.table("c:/rfr/r/test.txt") reads the text file "test.txt", which contains the following lines: 21437 21438 21419-2 21420-2 21421-2 21422-2 and produces the following result: > temp V1 1 21437+0i 2 21438+0i 3 0+0i 4 0+0i 5 0+0i 6 0+0i > These "numbers" are actually sample ID's, and I expected the presence of the hyphen would cause temp to be character or a factor, but it ends up as complex numbers. System info: platform i386-pc-mingw32 arch x86...

Hi, Am i doing something silly here in expecting Euler's formula to be handled by exp? exp( ix ) = cos x + i sin x. The first example below follows this, the others not. Thanks for the education! > exp( complex(real = 0, imag = 2*pi) ) [1] 1-0i > exp( complex(real = pi, imag = 2*pi) ) [1] 23.14069-0i > exp( complex(real = pi/2, imag = 0) ) [1] 4.810477+0i [[alternative HTML version deleted]]

...>> Rodrigo Zepeda <rzepeda17 at gmail.com> >>>>> on Fri, 17 Mar 2017 12:56:06 -0600 writes: > Dear all, > We seem to have found a "strange" behaviour in the hyperbolic tangent > function tanh on Windows. > When running tanh(356 + 0i) the Windows result is NaN + 0.i while on Mac > the result is 1 + 0i. It doesn't seem to be a floating point error because > on Mac it is possible to run arbitrarily large numbers (say tanh( > 999999677873648767519238192348124812341234182374817239847812738481234871823+0i)...