epconversions 0.2.1

Unit conversions for E+

epconversions

Unit conversions for E+

• Free software: Mozilla Public License 2.0 (MPL 2.0)

• Documentation: https://epconversions.readthedocs.io.

Energyplus has a bunch of conversion factors at the top of the Energy+.idd file. It looks like this:

! Default IP conversions (no \ip-units necessary)
!      $/(m3/s)               =>   $/(ft3/min)         0.000472000059660808
!      $/(W/K)                =>   $/(Btu/h-F)         0.52667614683731
!      $/kW                   =>   $/(kBtuh/h)         0.293083235638921
!      $/m2                   =>   $/ft2               0.0928939733269818
!      $/m3                   =>   $/ft3               0.0283127014102352
!      (kg/s)/W               =>   (lbm/sec)/(Btu/hr)  0.646078115385742
!      1/K                    =>   1/F                 0.555555555555556
!      1/m                    =>   1/ft                0.3048
!      A/K                    =>   A/F                 0.555555555555556
!      C                      =>   F                   1.8 (plus 32)
!      cm                     =>   in                  0.3937
!      cm2                    =>   inch2               0.15500031000062
!      deltaC                 =>   deltaF              1.8
!      deltaC/hr              =>   deltaF/hr           1.8
!      deltaJ/kg              =>   deltaBtu/lb         0.0004299
!      g/GJ                   =>   lb/MWh              0.00793664091373665
!      g/kg                   =>   grains/lb           7

Note the cm in the middle of that text snippet. It shows the conversion form cm to in and the multipier to use to convert

Features

The library epconversions has functions that will do these conversions:

from epconversions import epconversions

print(epconversions.convert2ip(100, 'cm'))
>> (39.37, 'in')

Can I convert to SI units ? Yes.:

epconversions.convert2si(100, 'in')
>> (254.00050800101602, 'cm')

What if I want only converted value. I don’t want the unit string:

epconversions.convert2si(100, 'in', unitstr=False)
>> 254.00050800101602

Nice !!

Why does it convert cm to in. Would it convert to m:

epconversions.convert2si(100, 'in', 'm')
>> (2.5399999999999987, 'm')

# for clarity
epconversions.convert2si(100, 'in', siunit='m')
(2.5399999999999987, 'm')

What are all the units it can convert in to ?:

epconversions.getsiunits('in')
>> {'cm', 'm'}

How do I know what it converts it to by default?:

epconversions.defaultsiunit('in')
>> 'cm'
epconversions.defaultsiunit('ft')
>> 'm'

What are all the units it can convert?:

epconversions.allsiunits()
>> ['$/(m3/s)',
'$/(W/K)',

<snip>

'A/K',
'C',
'cm',
'cm2',
'deltaC',
'deltaC/hr',
'deltaJ/kg',
'g/GJ',
'g/kg',
'g/MJ',


<snip>

'W',
'W/((m3/s)-Pa)',
'W/(m3/s)',
'W/K',
'W/m',
'W/m2',

<snip>

'years']

# around 128 now

# also try out ``allipunits()``

Thats all for now

Credits

This package was created with Cookiecutter and the audreyr/cookiecutter-pypackage project template.

History

2024-05-10

fixed issue #16

Problem:

convert2ip and convert2si do not convert strings to floats

Solution:

strings are converted to floats if possible

0.1.0 (2023-10-28)

• First release on PyPI.