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Barometer Decimal Places
Posted: Sat 20 Oct 2012 3:50 pm
by Buford T. Justice
I see after a search that a couple of years or so ago that those with Davis stations can display barometer readings going to thousandths if inHg and hundredths if hPa. It seems like Fine Offset also does this. I mean I can see barometric pressure in "alltime.ini"...
[Pressure]
highpressurevalue=30.3999996185303
highpressuretime=10/12/2012 9:55:00 AM
lowpressurevalue=29.3469142913818
lowpressuretime=10/17/2012 5:02:09 PM
(Yeah that was a hell of a drop and we had some really bad weather.)
So is there any hack for "Cumulus.ini" to display thousandths if inHg and hundredths if hPa if using a Fine Offset station?
Re: Barometer Decimal Places
Posted: Sat 20 Oct 2012 3:53 pm
by steve
Buford T. Justice wrote:So is there any hack for "Cumulus.ini" to display thousandths if inHg and hundredths in hPa if using a Fine Offset station?
No; Fine Offset stations supply pressure in hPa to 1 decimal place.
Re: Barometer Decimal Places
Posted: Sat 20 Oct 2012 3:57 pm
by Buford T. Justice
steve wrote:Buford T. Justice wrote:So is there any hack for "Cumulus.ini" to display thousandths if inHg and hundredths if hPa if using a Fine Offset station?
No; Fine Offset stations supply pressure in hPa to 1 decimal place.
What about inHg? It is going out to 13 decimal places.
Re: Barometer Decimal Places
Posted: Sat 20 Oct 2012 4:01 pm
by steve
Computers work in binary and can't store floating point decimals exactly. The numbers you see in the .ini files are the representations of the way the computer stores the number internally, because I use system routines to read and write the .ini files. When converting the binary values to decimal for display, I round them appropriately for the resolution of the weather station, i.e. 1 dp for hPa and 2 dp for inHg.
Re: Barometer Decimal Places
Posted: Sat 20 Oct 2012 4:10 pm
by Buford T. Justice
I see. Alright. Thanks Steve.
Re: Barometer Decimal Places
Posted: Sat 20 Oct 2012 4:14 pm
by Buford T. Justice
steve wrote:No; Fine Offset stations supply pressure in hPa to 1 decimal place.
I have suspected this because when in EasyWeather, one will see the relative and absolute pressures change at the same time all the time when using hPa but sometimes they don't when using inHg or mmHg.
Re: Barometer Decimal Places
Posted: Sun 21 Oct 2012 8:56 am
by cats_five
Buford T. Justice wrote:steve wrote:Buford T. Justice wrote:So is there any hack for "Cumulus.ini" to display thousandths if inHg and hundredths if hPa if using a Fine Offset station?
No; Fine Offset stations supply pressure in hPa to 1 decimal place.
What about inHg? It is going out to 13 decimal places.
That will be what happens converting hPa to inHg. Whatever you set the display to, the data is still recorded in hPa.