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Hi guys, may I propose standardizing convention of HubbleConstantNow in EnzoCosmology? In that file, HubbleConstantNow is in km/s/Mpc, but elsewhere in yt, it's in 100 km/s/Mpc:
pf['CosmologyHubbleConstantNow'] 0.65000000000000002
Hopefully this will prevent 10^2 problems in the future... like what I've been seeing until I discovered this discrepancy. _______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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Hi Stephen, I'm not sure how Britton feels about changing EnzoCosmology, but I assert that the parameter file does the Right Thing in that it returns exactly what's in the parameter file. What's in the parameter file is not the standard, unfortunately, but I think that the name "CosmologyHubbleConstantNow" is sufficiently communicative that it means give-me-whats-in-the-file. -Matt On Sat, Jun 20, 2009 at 9:13 AM, Stephen Skory<stephenskory@yahoo.com> wrote:
Hi guys,
may I propose standardizing convention of HubbleConstantNow in EnzoCosmology? In that file, HubbleConstantNow is in km/s/Mpc, but elsewhere in yt, it's in 100 km/s/Mpc:
pf['CosmologyHubbleConstantNow'] 0.65000000000000002
Hopefully this will prevent 10^2 problems in the future... like what I've been seeing until I discovered this discrepancy.
_______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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Guys, I need an idiot check. This is a unremarkable test simulation with star formation. Am I reading it correctly that according to the time calculations, yt thinks the last star was formed after 1.4 trillion years, not 14 billion years? Or am I doing something wrong? If I'm correct, there are some hubble value inconsistencies outside of EnzoCosmology, too?
pf = load('RedshiftOutput0005') sp = pf.h.sphere([0.5]*3,2.) yt INFO 2009-06-20 11:09:27,958 Adding Z_Field1 to list of fields yt INFO 2009-06-20 11:09:27,958 Adding Z_Field2 to list of fields ct = sp["creation_time"] yt INFO 2009-06-20 11:09:55,519 Getting field creation_time from 1172 print "%1.5e" % (max(ct) * pf["years"]) 1.45113e+12
_______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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Hi Stephen, I have a copy of RedshiftOutput0005. In mine, there are some parameters that seem a bit funny to me: InitialTime = 646.75066015177 Using pf.cosmology_get_units it returns that this means the start time was 1.45e12; same answer if you use lengthunits/velocityunits as the time unit. The creation time, in light of this, doesn't seem so bad. The current redshift is also zero, which I suppose means it's the final output. Can you tell us a bit more about this particular simulation and how you initialized it? -Matt On Sat, Jun 20, 2009 at 11:17 AM, Stephen Skory<stephenskory@yahoo.com> wrote:
Guys,
I need an idiot check. This is a unremarkable test simulation with star formation. Am I reading it correctly that according to the time calculations, yt thinks the last star was formed after 1.4 trillion years, not 14 billion years? Or am I doing something wrong? If I'm correct, there are some hubble value inconsistencies outside of EnzoCosmology, too?
pf = load('RedshiftOutput0005') sp = pf.h.sphere([0.5]*3,2.) yt INFO 2009-06-20 11:09:27,958 Adding Z_Field1 to list of fields yt INFO 2009-06-20 11:09:27,958 Adding Z_Field2 to list of fields ct = sp["creation_time"] yt INFO 2009-06-20 11:09:55,519 Getting field creation_time from 1172 print "%1.5e" % (max(ct) * pf["years"]) 1.45113e+12
_______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________ _______________________________________________ Yt-dev mailing list Yt-dev@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
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Matt,
I have a copy of RedshiftOutput0005. In mine, there are some parameters that seem a bit funny to me:
InitialTime = 646.75066015177
It might be a different RedshiftOutput0005 than what you have. I think InitialTime refers to the cycle for that dataset. I don't think it's fishy. For example, from a different dataset: [sskory@verne survey]$ foreach i (DD*/data*) foreach? grep InitialTime $i foreach? end InitialTime = 0.81651284465961 InitialTime = 1.2741637312563 InitialTime = 1.9883238421406 InitialTime = 3.1027599882949 InitialTime = 4.8418044994485 InitialTime = 7.464802895355 InitialTime = 11.648264071303 InitialTime = 18.175065018436 InitialTime = 27.945394051119 InitialTime = 43.581158022495 InitialTime = 67.695134170423 InitialTime = 101.45404286018 InitialTime = 129.59928291401 InitialTime = 157.03350432859 InitialTime = 184.17683070338 InitialTime = 212.12926974512 InitialTime = 243.14353477255 InitialTime = 274.89130484285 InitialTime = 305.4742180402 InitialTime = 338.66066939377 InitialTime = 374.32728867835 InitialTime = 409.95705670969 InitialTime = 447.42033595621 InitialTime = 489.45246826074 InitialTime = 531.35505518638 InitialTime = 574.17300563856 InitialTime = 622.77569114368 InitialTime = 646.75066015177
Can you tell us a bit more about this particular simulation and how you initialized it?
I did this a few years ago just testing some star formation parameters. I've attached the inits and parameter file. _______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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Hi Stephen, I recognize what InitialTime means. It means the time at which the dataset was taken. creation_time and InitialTime are largely in agreement. So I guess the "Time" conversion is wrong for "InitialTime" in your dataset. I note also that the RD0035 output from the lightcone run gives bad results as well. My runs give good results. Can you figure out where it came from? I have laid out the two avenues by which I have calculated it and gotten the same result. Maybe Britton, Sam or Brian can speak up. I get identical results using either utim as done by CosmologyGetUnits or length/velocity. As a sidenote, have you checked your parameter file versus your inits file? -Matt On Sat, Jun 20, 2009 at 11:48 AM, Stephen Skory<stephenskory@yahoo.com> wrote:
Matt,
I have a copy of RedshiftOutput0005. In mine, there are some parameters that seem a bit funny to me:
InitialTime = 646.75066015177
It might be a different RedshiftOutput0005 than what you have. I think InitialTime refers to the cycle for that dataset. I don't think it's fishy. For example, from a different dataset:
[sskory@verne survey]$ foreach i (DD*/data*) foreach? grep InitialTime $i foreach? end InitialTime = 0.81651284465961 InitialTime = 1.2741637312563 InitialTime = 1.9883238421406 InitialTime = 3.1027599882949 InitialTime = 4.8418044994485 InitialTime = 7.464802895355 InitialTime = 11.648264071303 InitialTime = 18.175065018436 InitialTime = 27.945394051119 InitialTime = 43.581158022495 InitialTime = 67.695134170423 InitialTime = 101.45404286018 InitialTime = 129.59928291401 InitialTime = 157.03350432859 InitialTime = 184.17683070338 InitialTime = 212.12926974512 InitialTime = 243.14353477255 InitialTime = 274.89130484285 InitialTime = 305.4742180402 InitialTime = 338.66066939377 InitialTime = 374.32728867835 InitialTime = 409.95705670969 InitialTime = 447.42033595621 InitialTime = 489.45246826074 InitialTime = 531.35505518638 InitialTime = 574.17300563856 InitialTime = 622.77569114368 InitialTime = 646.75066015177
Can you tell us a bit more about this particular simulation and how you initialized it?
I did this a few years ago just testing some star formation parameters. I've attached the inits and parameter file.
_______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________ _______________________________________________ Yt-dev mailing list Yt-dev@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
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I'll do some digging, but this is exactly what I wanted. An idiot check to find out where the problem was (me, the code or the dataset). Thanks! _______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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Hi guys, I think I figured it out -- my runs are right because I explicitly output TimeUnits. I think the "Time" calculation if you do not output it is incorrect -- I wrote it based on some bad information. I've committed a fix in r1352. -Matt On Sat, Jun 20, 2009 at 12:01 PM, Stephen Skory<stephenskory@yahoo.com> wrote:
I'll do some digging, but this is exactly what I wanted. An idiot check to find out where the problem was (me, the code or the dataset).
Thanks!
_______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________ _______________________________________________ Yt-dev mailing list Yt-dev@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
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I think I figured it out -- my runs are right because I explicitly output TimeUnits. I think the "Time" calculation if you do not output it is incorrect -- I wrote it based on some bad information. I've committed a fix in r1352.
Bingo! Thanks Matt! _______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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Matt,
I recognize what InitialTime means.
In light of your 'bad information' it appears we were talking perpendicular to each other here. I'm sorry if I patronized you! _______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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No worries, it's all good. :) On Sat, Jun 20, 2009 at 12:21 PM, Stephen Skory<stephenskory@yahoo.com> wrote:
Matt,
I recognize what InitialTime means.
In light of your 'bad information' it appears we were talking perpendicular to each other here. I'm sorry if I patronized you! _______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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Hey guys, I think Matt's right that pf['CosmologyHubbleConstantNow'] is simply taking what the parameter file is giving us, and that it's a good thing. When I implemented Cosmology.py and EnzoCosmology.py, I basically rewrote in python stuff that already existed. EnxoCosmology.py, being taken from enzo, originally did accept h [100 km/s/Mpc] (as opposed to H_0). Cosmology.py, on the other hand, took H_0. I figured it was important to standardize the input to those two sets of functions. Cosmology.py seemed a little more complicated, and I figured I had a higher chance of screwing it up, so I chose to change EnzoCosmology.py. It would be nice to have them consistent with the h that comes in from the parameter file, but if we do that, we'll need to be careful to fix everything that uses the cosmology functions so they aren't suddenly wrong. Britton On Sat, Jun 20, 2009 at 12:48 PM, Stephen Skory <stephenskory@yahoo.com>wrote:
Matt,
I have a copy of RedshiftOutput0005. In mine, there are some parameters that seem a bit funny to me:
InitialTime = 646.75066015177
It might be a different RedshiftOutput0005 than what you have. I think InitialTime refers to the cycle for that dataset. I don't think it's fishy. For example, from a different dataset:
[sskory@verne survey]$ foreach i (DD*/data*) foreach? grep InitialTime $i foreach? end InitialTime = 0.81651284465961 InitialTime = 1.2741637312563 InitialTime = 1.9883238421406 InitialTime = 3.1027599882949 InitialTime = 4.8418044994485 InitialTime = 7.464802895355 InitialTime = 11.648264071303 InitialTime = 18.175065018436 InitialTime = 27.945394051119 InitialTime = 43.581158022495 InitialTime = 67.695134170423 InitialTime = 101.45404286018 InitialTime = 129.59928291401 InitialTime = 157.03350432859 InitialTime = 184.17683070338 InitialTime = 212.12926974512 InitialTime = 243.14353477255 InitialTime = 274.89130484285 InitialTime = 305.4742180402 InitialTime = 338.66066939377 InitialTime = 374.32728867835 InitialTime = 409.95705670969 InitialTime = 447.42033595621 InitialTime = 489.45246826074 InitialTime = 531.35505518638 InitialTime = 574.17300563856 InitialTime = 622.77569114368 InitialTime = 646.75066015177
Can you tell us a bit more about this particular simulation and how you initialized it?
I did this a few years ago just testing some star formation parameters. I've attached the inits and parameter file.
_______________________________________________________ sskory@physics.ucsd.edu o__ Stephen Skory http://physics.ucsd.edu/~sskory/ <http://physics.ucsd.edu/%7Esskory/> _.>/ _Graduate Student ________________________________(_)_\(_)_______________
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participants (3)
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Britton Smith
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Matthew Turk
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Stephen Skory