similar to: format bug and patch

Should both parts 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 >

Hi, I want to print real numbers in C code with different values for digits. How to do that? As I have understood, what I should do is to call StringFromReal() which calls FormatReal(), that one suggests the parameters (width, decimal places and exponential form). FormatReal() includes eps = pow(10.0, -(double)R_print.digits); So I guess I have to change the value of R_print.digits.

Hi! I have iBook G4, I was installed on this openSuSe 11.1 ppc, and I whant to install wine 1.0.1. In the whine repositories no wine for ppc architecture. I downloaded source tar.bz2 file, configuring finished succesed, but compiling, when process with file dlls/mshtml.tbl, exiting with error: error: get_type_vt: unknown type: 0x2b. Hou fix it :(

On a system with IEEE_754 undefined, I run into an bug, when the value of an element of the first argument (e.g., x[0]) of formatReal() is NA: 1. (format.c:235) if (!R_FINITE ..) gives nanflag=1 (!naflag remains 0) 2. (format.c:272..288) *m gets an value of -2147483643 (from the format fiddling, should not matter to us) 3. (format.c:289) because naflag is zero, m does not

Full_Name: Pierre Legendre Version: 2.1.1 OS: Mac OSX 10.4.3 Submission from: (NULL) (132.204.120.81) I am reporting the mis-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):

The IEEE floating point standard allows for negative zero, but it's hard to know that you have one in R. One reliable test is to take the reciprocal. For example, > y <- 0 > 1/y [1] Inf > y <- -y > 1/y [1] -Inf The other day I came across one in complex numbers, and it took me a while to figure out that negative zero was what was happening: > x <-

atan(1i) -> 0 + Inf i complex(1/5) -> 0.2 + 0i atan(1i) -> (0 + Inf i) * (0.2 + 0i) -> 0*0.2 + 0*0i + Inf i * 0.2 + Inf i * 0i infinity times zero is undefined -> 0 + 0i + Inf i + NaN * i^2 -> 0 + 0i + Inf i - NaN -> NaN + Inf i I am not sure how complex arithmetic could arrive at another answer. I advise against messing with infinities... use atan2() if you don't

> complex(real = 0, imaginary = Inf) [1] 0+Infi > Inf*1i [1] NaN+Infi >> complex(real = 0, imaginary = Inf)/5 [1] NaN+Infi See the Note in ?complex for the explanation, I think. Duncan can correct if I'm wrong. -- Bert On Thu, Sep 5, 2024 at 3:20?PM Leo Mada <leo.mada at syonic.eu> wrote: > Dear Bert, > > These behave like real divisions/multiplications: >

>>>>> Richard O'Keefe >>>>> on Fri, 6 Sep 2024 17:24:07 +1200 writes: > The thing is that real*complex, complex*real, and complex/real are not > "complex arithmetic" in the requisite sense. > The complex numbers are a vector space over the reals, Yes, but they _also_ are field (and as others have argued mathematically only

Dear Peter, thank you very much for your answer. My problem is that I need to calculate the following quantity: solve(chol(A)%*%Y) Y is a 3*3 diagonal matrix and A is a 3*3 matrix. Unfortunately one eigenvalue of A is negative. I can anyway take the square root of A but when I multiply it by Y, the imaginary part of the square root of A is dropped, and I do not get the right answer. I tried

G.5.1 para 2 can be found in the C17 standard -- I actually have the final draft not the published standard. It's in earlier standards, I just didn't check earlier standards. Complex arithmetic was not in the first C standard (C89) but was in C99. The complex numbers do indeed form a field, and Z*W invokes an operation in that field when Z and W are both complex numbers. Z*R and R*Z,

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(

The thing is that real*complex, complex*real, and complex/real are not "complex arithmetic" in the requisite sense. The complex numbers are a vector space over the reals, and complex*real and real*complex are vector*scalar and scalar*vector. For example, in the Ada programming language, we have function "*" (Left, Right : Complex) return Complex; function "*" (Left :

Is there an easy way to compare complex numbers? Here is a small example: > (z1=polyroot(c(1,-.4,-.45))) [1] 1.111111-0i -2.000000+0i > (z2=polyroot(c(1,1,.25))) [1] -2+0i -2+0i > x=0 > if(any(identical(z1,z2))) x=99 > x [1] 0 # real and imaginary parts: > Re(z1); Im(z1) [1] 1.111111 -2.000000 [1] -8.4968e-21 8.4968e-21 > Re(z2); Im(z2) [1] -2

It works! But Once I have the square root of this matrix, how do I convert it to a real (not imaginary) matrix which has the same property? Is that possible? Best, Simon >----Messaggio originale---- >Da: p.dalgaard at biostat.ku.dk >Data: 21-nov-2009 18.56 >A: "Charles C. Berry"<cberry at tajo.ucsd.edu> >Cc: "simona.racioppi at

On 'factor', I meant the case where 'levels' is not specified, where 'unique' is called. > factor(c(complex(real=NaN), complex(imaginary=NaN))) [1] NaN+0i <NA> Levels: NaN+0i Look at <NA> in the result above. Yes, it happens in earlier versions of R, too. On matching both NA and NaN, another consequence is that length(unique(.)) may depend on order.

Hi, > 1e10+5i [1] 1e+10+0e+00i > Im(1e10+5i) [1] 5 maybe little better... --- R-3.5.1.orig/src/main/complex.c 2018-03-26 07:02:25.000000000 +0900 +++ R-3.5.1/src/main/complex.c 2018-07-10 12:50:42.523874767 +0900 @@ -381,6 +381,7 @@ r->i = fround(pow10 * x->i, digits)/pow10; } else { digits = (double)(dig); + if(digits < 1) digits=1; /* a little better */

Hi, It is my understanding that the eigenvectors of a circulant matrix are given as follows: 1,omega,omega^2,....,omega^{p-1} where the matrix has dimension given by p x p and omega is one of p complex roots of unity. (See Bellman for an excellent discussion on this). The matrix created by the attached row and obtained using the following commands indicates no imaginary parts for the

Dear friends, I run the Gelman-Rubin Convergence test for a MCMC object I have and I got the following result Multivariate psrf 1.07+0i, What does this mean? I guess (if I am not mistaken) that I should get a psrf close to 1.00 but what is 1.07+0i? Is that convergence or something else? Jorge [[alternative HTML version deleted]]

Function factor() in the current development version (2009-05-22) guarantees that levels are different character strings. However, they may represent the same decimal number. The following example is derived from a posting by Stavros Macrakis in thread "Match .3 in a sequence" in March nums <- 0.3 + 2e-16 * c(-2,-1,1,2) f <- factor(nums) levels(f) # [1]