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Double precision
Yes, that's what I was thinking too, before seeing the benchmarks in quad precision. See for example: http://people.sc.fsu.edu/~burkardt/f_src/linpack_bench/linpack_bench.html or http://www.siam.org/meetings/la03/proceedings/hhasegaw.pdf But, despite its extreme slowness it is possibly the... -
Double precision
Yes, but multiple systems of reference (SR) which contain a subset of commonly shared particles simulated at once are needed here since clusters of stars have to be considered, and stars migrate. See e.g. http://uwnews.org/article.asp?articleID=43593 and take a look at the mpg video linked at... -
Double precision
Yes, indeed. But benchmarks show that quad precision can be 10 to 100 times slower than double! This, becaue it is done via internal software, it is not hardwired on the cpu. So, that would lead to unacceptable execution times. I would have been happy with "only" 23 s.f., and really wonder why... -
Double precision
Hmmm... for "real (kind=16) :: var" it tells me: "Kind 16 not supported for type Real". :-( -
Double precision
xwb, with kind=10 on GNU Fortran compiler I don't get more than 18 digits precision. I can see that subtracing two almost equal numbers. Don't have Visual Fortran, but I assume 80-bit should have more (it depends on how the mantissa and range are distributed internally of course). But I would be... -
Double precision
Well.. I maybe forced to resort to a single star-centered system in a way or another. But, as I said, that would prevent me to generalize the simulation to comet orbits moving in star clusters (not only around a single star), i.e. undergoing the gravitational pull in multiple star systems, which... -
Double precision
XWB: My compiler accepts kind=10, but it remains double precision. -
Double precision
Yes, that's what I have heard too! Does anybody know how to do that? Any reference? Meanwhile, here is my problem... I have to integrate the orbit of a comet around a star which itself orbits in the Galaxy. How big is the Galaxy? Huge... it depends. For example lets take the sun's orbit as... -
Double precision
Oh, yes... thanks. :-) BTW, would triple precision be possible? -
Double precision
Sorry, but I'm a newbie with Fortran.... so I don't get it why the following program continues to evaluate x as a single precision variable? Why are there non zero decimals? Mark. ----------------------------------------- program precision_test implicit none integer, parameter :: sgl =...
