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Mar 21	comment	How to have Mathematica find asymptotics with correct asumptions So why does `Evaluate[Gamma[-2]/Gamma[-1]]` in Mathematica give complex infinity? How could I make Mathematica spit out a complex number instead?
Mar 21	comment	How to have Mathematica find asymptotics with correct asumptions @whuber thanks. I was looking for $x\to\infty$ limit rather than $x\to 0$. Could you give me some more info about what your first line is doing here? as for your second line are you suggesting that this ratio is infact quite well defined?
Mar 21	asked	How to have Mathematica find asymptotics with correct asumptions
Mar 10	revised	Launching remote slave kernels on HPC causes slow down added 921 characters in body
Mar 10	comment	Launching remote slave kernels on HPC causes slow down You are probably right. What a shame if this is the case, I could have lived with it being a little bit slower, but not this much slower.
Mar 10	comment	Launching remote slave kernels on HPC causes slow down @Ajasja I haven't tried it, but it can't hurt so I will give that a go next, thanks.
Mar 9	comment	Mathematica Parellelization on HPC @OleksandrR. I think you are right MathLink does seem to be dying for me with 190 Kernels. Despite getting there in the end it now takes vastly longer than when I had 19 single MathKernels with 10 local slaves each.
Mar 9	revised	Launching remote slave kernels on HPC causes slow down added 104 characters in body
Mar 9	asked	Launching remote slave kernels on HPC causes slow down
Mar 6	comment	Efficient way to utilise Parallel features to make use of many cores @Szabolcs thanks, this is going to save me a lot of time.
Mar 6	accepted	Efficient way to utilise Parallel features to make use of many cores
Mar 6	comment	Efficient way to utilise Parallel features to make use of many cores the matrix of pairs and `ParallelMap` might just be the way to go, thanks.
Mar 6	comment	Efficient way to utilise Parallel features to make use of many cores @Szabolcs Yep, that is the problem. Is there no way around this then?
Mar 5	comment	Mathematica Parellelization on HPC @Szabolcs Hi, I finally got this working. I don't know much about Package writing, so have just placed my needed Kernel Launch commands in `job.nb` along with parsing commands for `hostfile`. If I try to use your package as a template then add it to my notebook with `Needs` things no longer work for some reason. I don't know much about package writing so I am prob doing something stupid there. If you like however I can make a package from my notebook and upload to bitbucket and perhaps you could take a look so we could publish it there for others using `PBSpro` in the future?
Mar 5	asked	Efficient way to utilise Parallel features to make use of many cores
Feb 28	comment	Mathematica Parellelization on HPC @Szabolcs totally baffled as to why it's giving `bash: math: command not found` when I am passing the absolute path to `math` everywhere I can in `CRC.m`. Also even from the terminal simply doing `ssh node055 /cm/shared/apps/Mathematica_8.0.4/bin/math` gives the familiar `Input[]` but then times out after 15 secs.
Feb 27	comment	Mathematica Parellelization on HPC I defined `ssh="/usr/bin/ssh" already in place of your` rsh` def.
Feb 27	comment	Mathematica Parellelization on HPC I do think I understand it reasonably well now, although I am a little rusty on some Mathematica syntax to do with string joins etc. How is; SubKernels`RemoteKernels`RemoteMachine[ host, ssh <> " -x -f -n `1` \"" <> "/cm/shared/apps/Mathematica_8.0.4/bin/math" <> " -mathlink -linkmode Connect `4` -linkname '`2`' -subkernel -noinit\"", 16]? On these HPC `math` is not an alias and full path is needed- the error I now get is `bash: math: command not found KernelObject::rdead: Subkernel connected through remote[node053] appears dead.` (with or without abs path in above)
Feb 27	comment	Mathematica Parellelization on HPC `ParallelTable::nopar: No parallel kernels available; proceeding with sequential evaluation.` is what I get now. With my hostfile in the above format, I changed things in `CRC.m` to be like `hosts = Import[hostfile, "List"]; $ConfiguredKernels = Join[$ConfiguredKernels, CRCKernel @@@ Rest[hosts]]` and changed `CRCKernel` to CRCKernel[host_String]:= SubKernels`RemoteKernels`RemoteMachine[ host, ssh -x -f <> " -n `1` \"" <> math <> " -mathlink -linkmode Connect `4` -linkname '`2`' -subkernel -noinit\"", 16] as well as the original definition.
Feb 27	comment	Mathematica Parellelization on HPC Ah, it just contains one column with `node053 node055,.....` the number of cores is always 16 though, so I can put that in manually by just removing the second arg of `CRC`.