How do I change the number of displayed decimal places?

[Wayne Rademacher]

Hi,

I would like to know if there is a way to change the displayed decimal places of an observation.   I have searched the WeeWX setup and user guides, I have also stepped through my weewx.conf file but can't seem to find out how this is done.

I have attached a screen shot showing my current display.   I would like to trim off (4) digits from both Brightness and Battery.  I am new to this group so please let me know if I need to supply more or different information. 

windBatteryStatus = Battery

luminosity (luxXXX)  = Brightness

Here is my PWS configuration:

• WeatherFlow Tempest
• WeeWX Ver 4.10.2
• Belchertown Skin Ver. 1.3
• Pi4

Thanks,

Wayne

[vince]

You'd have to share how you made that Brightness and Battery stuff appear in the skin, was there an .inc file possibly ?

You might look at your skin.conf [[StringFormats]] section and add entries there for whatever units your Brightness and Battery are set to use and set the format there.

[Karen K]

@vince: That is the Belchertown skin. The area schown in the screenshot is configured in a single entry in skin.conf, listing the observation types to be displayed. There is no special configuration for decimal places available. So the general configuration of WeeWX applies.

[Wayne Rademacher]

To display the data, I simply added the observation title from my sensor map to the "station_observations" string in the weewx.conf file.

Since I was able to change the name of the observation (i.e. luminosity to Brightness) I was hoping the data could also be formatted.  I included snippets from my weewx.conf file that shows how I got the information to show up on the belchertown screen.

Regards,

Wayne 

station_observations = "barometer","dewpoint","outHumidity","rain", "luminosity", "UV", "cloud_cover", "windBatteryStatus"

[[sensor_map]]
        outTemp = air_temperature.ST-00105xxx.obs_st
        outHumidity = relative_humidity.ST-00105xxx.obs_st
        pressure = station_pressure.ST-00105xxx.obs_st
        lightning_strikes = lightning_strike_count.ST-00105xxx.obs_st
        avg_distance = lightning_strike_avg_distance.ST-00105xxx.obs_st
        outTempBatteryStatus = battery.ST-00105xxx.obs_st
        windSpeed = wind_speed.ST-00105xxx.rapid_wind
        windDir = wind_direction.ST-00105xxx.rapid_wind
        luminosity = illuminance.ST-00105xxx.obs_st
        UV = uv.ST-00105xxx.obs_st
        rain = rain_accumulated.ST-00105xxx.obs_st
        windBatteryStatus = battery.ST-00105xxx.obs_st
        radiation = solar_radiation.ST-00105xxx.obs_st
        lightningXXX = distance.ST-00105xxx.evt_strike
        lightningYYY = energy.ST-00105xxx.evt_strike

[[[Labels]]]
            # Users frequently change the labels for these observation types
            [[[[Generic]]]]
                  windBatteryStatus = Battery
                  luminosity    = Brightness
                # inHumidity     = Inside Humidity

[vince]

For this original question:

• you're using luminosity and windBatteryStatus which are in the db schema
• but I can't see how to determine what they map to by default
• so I can't suggest which [[StringFormats]] edits to make in skin.conf

This is one where there might not be a simple example documented as far as I can tell.

• how do you know which [Units] [[Groups]] category a db element is mapped to by default ?
• how do you change which category a db element is mapped to ?
• how can you (can you?) add a new units group if the default units don't have anything that matches your needs ?

[an oldman]

Hi

this is how i did it.

using WeeWX version: 4.10.1 Seasons version: 4.10.1 Python version: 3.10.10

in the user dir is a file extensions.py

i add

import weewx.units

weewx.units.obs_group_dict['windBatteryStatus'] = 'group_boolean'

weewx.units.obs_group_dict['luminosity'] = 'group_illuminance'

then restart weewx

hope this helps

[Karen K]

I guess `windBatteryStatus` is not a boolean value (i.e. true or false) but an integer or real value. So you may want to choose another observation group.

The decimal places are set in section [[[[StringFormats]]]] for the respective units (not observation groups).

[Wayne Rademacher]

It works!!!

Thanks everyone,

Wayne

Here are the required changes:

I added this to extensions.py as suggested by an oldman and Karen K

/usr/share/weewx/user extensions.py

import weewx.units

weewx.units.obs_group_dict['windBatteryStatus'] = ''group_volt'
weewx.units.obs_group_dict['luminosity'] = 'group_illuminance'

I changed the [[stringformats]] in the belchertown skin.conf to get the right amount of digits.

    [[StringFormats]]

        #volt                   = %.1f

        volt                    = %.2f

[vince]

Wow - I never put the pieces together in my brain before.  Thanks for replying with what you did rather than just "solved".

Anybody willing to volunteer adding a brief wiki page for this one ?  It seems like a great example to use for mapping something to a particular units group, as well as editing the string format.

[gjr80]

Perhaps not in the exact words of this issue, but the Customising units and unit group section in the Customisation Guide covers pretty much everything in this thread.

Gary

[Wayne Rademacher]

I had previously looked through the customization guide but failed to realize the usefulness of the information.    After working through this practical exercise, I revisited the customization guide and a light bulb came on!    I now have a much better understanding of the weewx customization innerworkings.

Perhaps this exercise will help others that are struggling with system customization.

Wayne