[Info-vax] Where is EISNER:: and who funds it?

[George Cornelius]

In article <sqa4av$v1r$1 at news.misty.com>, Johnny Billquist <bqt at softjar.se> writes:
> On 2021-12-26 00:33, Dave Froble wrote:
>> On 12/25/2021 6:05 PM, Johnny Billquist wrote:
>>> On 2021-12-24 04:09, alanfe... at gmail.com wrote:
>>>> Anyway, regarding Fahrenheit: Americans aren't switching to the 
>>>> "standard,"
>>>> Celsius, for the same reason you're not using a Dvorak keyboard. 
>>>> Actually, if
>>>> you want to go all the way you should be using Kelvin, the only "true"
>>>> temperature scale in use.
>>>
>>> Kelvin and Celsius is easy to move between. It's just an offset 
>>> difference.
>>>
>>> Â  Johnny
>> 
>> As far as that goes, so is Fahrenheit with either.  It's just a 
>> multiplier and an offset.
> 
> Of course. But that multiplier is what makes it uglier. Yes, sure, 
> anyone can do it. But it's much less straight forward. And you have two 
> different offsets for C and K when you come from F.

You forgot Rankine.

But I'll /weigh/ in on the conversion equation.

For mnemonic purposes, this set of equations is a dream (and compilers 
are free to optimize away the extra addition or subtraction):

 F = ( C + 40 ) * f1 - 40

 C = ( F + 40 ) * f2 - 40

where f1 and f2 are the usual conversion factors.

I find it easy to remember the -40 fixed point for these conversions
because my metal shop teacher once talked about molding hammers of
mercury and cooling them, once poured, to -40, Celsius or Fahrenheit.

George

 
> Everything is just math in the end. Nothing strange to see here. It's 
> just a question of how much do you need to remember and compute.
> 
>> A couple of lines from a simple VB program I have:
>> 
>>  Â Â Â  C = (F - 32) * 5 / 9
>>  Â Â Â  F = C * 9 / 5 + 32
>> 
>> If I remember correctly (always questionable anymore) for Kelvin the 
>> additional constant would be 273.  Maybe not.
> 
> 273.15 unless I remember wrong. (Checked - I remembered right.)
> So if you have C, add 273.15 and you have K.
> Of course, in most cases, just 273 is good enough.
> 
>    Johnny