Unit Definitions
futureboy.us
Unit Definitions
1–10 of 26 posts
Re: Unit Definitions
#2This looks like an older version of the file. I don't know where to find an easily-linkable online copy of the current one, but it's the "definitions.units" file included in GNU Units.
Re: Unit Definitions
#3This looks like an older version of the file. I don't know where to find an easily-linkable online copy of the current one, but it's the "definitions.units" file included in GNU Units.
http://fossies.org/linux/units/definitions.units
home page at https://www.gnu.org/software/units/
full source code at http://ftp.gnu.org/gnu/units/
Re: Unit Definitions
#4This looks like an older version of the file. I don't know where to find an easily-linkable online copy of the current one, but it's the "definitions.units" file included in GNU Units.
Latest release: http://ftp.gnu.org/gnu/units/units-2.12.tar.gz
Link for the lazy: https://gist.github.com/phaer/44bd758154fca29d6b38
Re: Unit Definitions
#5This looks like an older version of the file. I don't know where to find an easily-linkable online copy of the current one, but it's the "definitions.units" file included in GNU Units.
It overlaps with it a great deal, but it is not simply that file. Quoting:
This file is adapted, modified, and extended from the units database for use with GNU units, a units conversion program by Adrian Mariano adrian@cam.cornell.edu, who did a damn fine job collecting much of this.
Re: Unit Definitions
#6This looks like an older version of the file. I don't know where to find an easily-linkable online copy of the current one, but it's the "definitions.units" file included in GNU Units.
It overlaps with it a great deal, but it is not simply that file. Quoting: This file is adapted, modified, and extended from the units database for use with GNU units, a units conversion program by Adrian Mariano adrian@cam.cornell.edu, who did a damn fine job collecting much of this.
The most important modification being the editorializing, which is most of the value to be found in reading this version. :-)
Re: Unit Definitions
#7> This means that, if you follow the rules of the SI, 1 Hz = 1/s = 1 radian/s
I fail to see how this follows from the SI definition of either the hertz or the radian.
Re: Unit Definitions
#8In regards to the difference between American and European billion/trillion/etc:
// These number terms were described by N. Chuquet and De la Roche in the 16th
// century as being successive powers of a million. These definitions are
// still used in most European countries. The current US definitions for these
// numbers arose in the 17th century and don't make nearly as much sense.
By the time "billion" was defined by Chuquet and De la Roche, the concepts of "ten thousand" and "hundred thousand" were in widespread use. Those were followed by "million". So there's already a precedent for "we multiply things by a hundred before coming up with a new name". How does it make sense to change that to "but after a point, we multiply things by a thousand before coming up with a new name"?
I could see a couple systems that would arguably make more sense:
* ten, hundred, thousand, million, billion, trillion... (no multipliers)
* ten, hundred, ten hundred, thousand, ten thousand, hundred thousand, million, ten million, hundred million, thousand million, billion..., million billion, trillion... (use all previous multipliers before creating the next new name)
Admittedly, the US uses neither of those systems. But sticking with the precedent of "a hundred is the highest multiplier" makes sense.
Re: Unit Definitions
#9This looks like an older version of the file. I don't know where to find an easily-linkable online copy of the current one, but it's the "definitions.units" file included in GNU Units.
It overlaps with it a great deal, but it is not simply that file. Quoting: This file is adapted, modified, and extended from the units database for use with GNU units, a units conversion program by Adrian Mariano adrian@cam.cornell.edu, who did a damn fine job collecting much of this.
Ah, I see. Yes, I'd missed the editorializing -- which I do think is worth reading (especially about the candela), now that it's been pointed out (though I do think he's wrong about bits and Hertz). For what it's worth, though, it appears to be modified from an older version of the file; some of the editorializing would be out of date if it used an up-to-date version.
Re: Unit Definitions
#10In regards to the difference between American and European billion/trillion/etc: // These number terms were described by N. Chuquet and De la Roche in the 16th // century as being successive powers of a million. These definitions are // still used in most European countries. The current US definitions for these // numbers arose in the 17th century and don't make nearly as much sense. Huh? Admittedly I'm biased, being…
I think the "making sense" refers to the fact that "billion" has "bi-" as a prefix, and "trillion" has "tri-" as a prefix. In American English, it's not clear what is "bi-", exactly, about a billion -- two of what?
If we had skipped "billion" and gone with "trillion" = 1e9, then it would be more natural, because then it would refer to the number of thousands; but then the more natural nomenclature would be "bi-sands" and "tri-sands" or something.