This component applies the loading correction implemented by Ray Weiss for the Radiance Research PSAP. This correction consists of dividing the absorptions by a polynomial of the corresponding transmittance. Under normal circumstances, this polynomial is just a slope and intercept. That is, the normal form of the correction is: out = in / (A + B * Tr)

Usage

da.corr.weiss [switches…​] [[station] variables times [archive]|[file]]

Switches

--constants=COEFFICIENTS…​

This calibration set the transformation applied to the transmittances to generate the correction factor.

Default: 0.814,1.237

--correct-absorption=SELECTION

These are the variables that the correction is applied to. Correcting using more than one transmittance for all absorptions is only supported using the suffixes option or by leaving this option unset (using all suffixes).

Default: All absorptions

--instruments=SUFFIX…​

These are the instrument suffixes to correct. For example A11 would usually specifies the main absorption instrument. This option is mutually exclusive with manual variable specification.

Default: All instrument suffixes

--reverse[=BOOLEANS]

When enabled, this causes the correction to be run in reverse. This is used to back out the correction as applied by the PSAPs in their hardware.

--transmittance-end=INPUT

This is the input end transmittance used in the correction. When this option is set, this transmittance is used for all absorption channels. Therefor, normally only a single absorption can be corrected while using this option.

Default: Resolved automatically by instrument suffix

--transmittance-start=INPUT

This is the input start transmittance used in the correction. When this option is set, this transmittance is used for all absorption channels. Therefor, normally only a single absorption can be corrected while using this option.

Default: Resolved automatically by instrument suffix

Arguments

If no bare word input specification is supplied then data are read from standard input.

station

This argument is used to specify the station used to look up variables that do not include a station as part of an archive read specification. The station is the three letter GAW station code of the location, such as BND. The argument accepts multiple stations specified as regular expressions and separated by : or ; or ,. For example BND,MLO and (BND|MLO) are two ways of selecting both the BND and MLO stations.

The special value allstations may also be specified to select all stations.

variables

This argument may be split into multiple actual program arguments. Each part consists of one or more variable specifications separated by , (commas). The station and archive used if none are explicitly given are defined in the other arguments or inferred from system defaults. For example simply BsB_S11 selects the blue scattering from the S11 instrument and returns all cut sizes and metadata. If instead ::BsB_S11:pm10 is used then only PM10 scattering is returned. That is, the selection specifies "any" station and archive (the defaults are set in the other arguments) then requires that it has the "PM10" flavor. A specification such as bnd:BsB_S11,thd:BsB_S11 allows for data selection from multiple stations.

This may also be used to select a "record" type alias such as "S11a". In this mode all the variables defined in the alias are returned.

Finally the special value everything can be used to select all available data for the given station(s) and archive(s).

times

This argument may be split into multiple actual program arguments. This full list of time arguments defines a time bounds list that sets the range of data queried. The final resulting data are clipped to the given time bounds but any values that intersect them are returned.

archive

This argument is used to specify the archive used to look up variables that do not include an archive as part of an archive read specification. The archive is the internal name, such as raw or clean_meta. The argument accepts multiple archives specified as regular expressions and separated by : or ; or ,. For example raw(_meta)? selects both the raw and raw_meta archives.

The special value allarchives may also be used to select all available archives.

file

This argument is used to specify the the file to read data from. If it is present and exists then data is read from the given file name instead of from standard input. Alternatively - (a single dash) may be used to explicitly specify standard input.

Examples

Defaults

This will correct all absorptions present in the input data. The transmittance for each absorption is resolved by looking for one with the same end suffix as the absorption. For example, BaG_A11 uses IrG_A11 as its transmittance.

da.corr.weiss bnd S11a 2015-05-01 2015-05-03

Or:

da.corr.weiss input_file.c3d

Or:

da.get bnd S11a 2015-05-01 2015-05-03 | da.corr.weiss
Single instrument with alternate constants

This will correct all absorptions from the A11 instrument using the alternate constants A=0.866 and B=1.317.

da.corr.weiss --constants=0.866:1.317 --instruments=A11 bnd S11a 2015-05-01 2015-05-03
Single variable with alternate transmittance

This will correct only the variable BaG_A11 and specifies an alternate transmittance (IrR_A11) to correct it with.

da.corr.weiss --correct-absorption=bnd:raw:BaG_A11 --transmittance-start=bnd:raw:IrR_A11 bnd S11a 2015-05-01 2015-05-03