Recipe inputs

Input types are defined in arkimapslib/inputs.py, and this is their reference manual.

When defined in yaml recipes, an input can a dict defining the input for all models, or a list of dict defining the input differently depending on the model.

Input types such as cat can be derived from one or more other inputs by computation, and Arkimaps will handle the chain of dependencies correctly.

Inputs can be defined anywhere in the recipe directory, and dependencies between them will be handled correctly.

Input definition

An input has a name, a type, optionally a model, optionally some notes for the documentation, and other keywords depending on the type.

This is an example input definition for a recipe, with an input valid for any model:

inputs:
  sf:
    - model: ifs
      arkimet: product:GRIB1,98,128,144
      eccodes: shortName is "sf"

This is an example input definition that matches GRIBs differently depending on the model that generated the data:

inputs:
  tp:
    - model: cosmo
      arkimet: product:GRIB1,,2,61
      eccodes: centre != 98 and shortName is "tp"
    - model: ifs
      arkimet: product:GRIB1,98,128,228
      eccodes: centre == 98 and shortName is "tp"

This is an example input definition that processes GRIBs differently depending on the model that generated the data:

inputs:
  sf:
    - model: ifs
      arkimet: product:GRIB1,98,128,144
      eccodes: shortName is "sf"
  snowcon:
    - model: cosmo
      arkimet: product:GRIB1,,2,78
      eccodes: shortName is "snow_con" or shortName is "snoc"
  snowgsp:
    - model: cosmo
      arkimet: product:GRIB1,,2,79
      eccodes: shortName is "snow_gsp" or shortName is "lssf"
  snowsum:
    - model: cosmo
      type: vg6d_transform
      args: ["--output-variable-list=B13205"]
      inputs: [snowcon, snowgsp]
  snowcosmo:
    - model: cosmo
      type: or
      inputs: [snowsum, snowgsp]
  snowdec1h:
    - model: cosmo
      type: decumulate
      step: 1
      inputs: snowcosmo
    - model: ifs
      type: decumulate
      step: 1
      inputs: sf

Inputs are referenced by name. They can be defined in the same file as recipes, but don’t need to, and recipes can reference inputs defined in any other yaml file.

Input type reference

default

A GRIB matched from the stream of data to be processed. The arkimet keyword defines an arkimet matcher, and the eccodes keyword defines a grib_filter expression, that select data from a stream of model output.

Example:

t2m:
 - model: cosmo
   arkimet: product:GRIB1,,2,11;level:GRIB1,105,2
   eccodes: centre != 98 and shortName is "2t" and indicatorOfTypeOfLevel == 105 and timeRangeIndicator == 0 and level == 2
 - model: ifs
   arkimet: product:GRIB1,98,128,167;level:GRIB1,1
   eccodes: centre == 98 and shortName is "2t" and indicatorOfTypeOfLevel == 1 and level == 0 and timeRangeIndicator == 0
 - model: erg5
   arkimet: product:GRIB2,00200,000,000,000,004,000;level:GRIB2S,103,003,0000001800
   eccodes: shortName is "t" and level == 2

If you define inputs differently depending on models, please make sure that the filter expression can discriminate the model. In the example above, if you defined eccodess simply as shortname is "2t" for both Cosmo and IFS, then you might end up with a temperature from IFS that is postprocessed using the Cosmo postprocessing.

static

References a file distributed with Arkimaps.

Example:

puntiCitta:
  type: static
  path: puntiCitta.geo

shape

References a shapefile distributed with Arkimaps.

Example:

sottozoneAllertaER:
  type: shape
  path: shapes/Sottozone_allerta_ER

One cannot use static for shapefiles, because shapefiles are actually directories.

cat

For each level for which all inputs are available, it creates a new GRIB by concatenating the GRIB data listed as inputs.

Example:

uv10m:
  type: cat
  inputs: [u10m, v10m]

decumulate

Performs decumulation using vg6d_transform.

The output of vg6d_transform_is split by step using ecCodes’ endStep, and stored in the pantry as $name+$step.grib.

Example:

inputs:
 tp:
   - model: cosmo
     arkimet: product:GRIB1,,2,61
     eccodes: centre != 98 and shortName is "tp"
   - model: ifs
     arkimet: product:GRIB1,98,128,228
     eccodes: centre == 98 and shortName is "tp"
 tpdec1h:
   - type: decumulate
     step: 1
     inputs: tp
 tpdec3h:
   - type: decumulate
     step: 3
     inputs: tp

average

Performs averaging using vg6d_transform.

The output of vg6d_transform_is split by step using ecCodes’ endStep, and stored in the pantry as $name+$step.grib.

Example:

inputs:
  t2mavg:
    - type: average
      step: 24
      inputs: t2m

vg6d_transform

Runs vg6d_transform run on another input, with arguments taken from the input definition.

The output of vg6d_transform_is split by step using ecCodes’ endStep, and stored in the pantry as $name+$step.grib.

Example:

wspeed10m:
  type: vg6d_transform
  args: ["--output-variable-list=B11002"]
  inputs: [u10m, v10m]

or

Choose the first available in a list of possible inputs. This can be used to implement values that can be computed in different ways depending on available input values.

Example:

snowcon:
  - model: cosmo
    arkimet: product:GRIB1,,2,78
    eccodes: shortName is "snow_con" or shortName is "snoc"
snowgsp:
  - model: cosmo
    arkimet: product:GRIB1,,2,79
    eccodes: shortName is "snow_gsp" or shortName is "lssf"
snowsum:
  - model: cosmo
    type: vg6d_transform
    args: ["--output-variable-list=B13205"]
    inputs: [snowcon, snowgsp]
snowcosmo:
  - model: cosmo
    type: or
    inputs: [snowsum, snowgsp]

In this case, if convective snow has been computed, it is added to large scale. Otherwise, just large scale is used.

groundtomsl

Given two inputs, assume that:

• the first is ground geopotential, and that it is only computed for step 0

• the second is a value computed for all step and measured as height above ground

The two values are combined to convert the second value to a value above mean sea level.

grib_set and clip are applied if present.

Due to internal optimization, the second input value is not available in the clip expression.

Example:

hzero:
 - model: ifs
   type: groundtomsl
   inputs: [z, hzeroground]
   clip: "hzero[hzero <= z] = -999"
   grib_set:
     shortName: deg0l

sffraction

Compute snow fraction percentage on total precipitation.

Given two inputs, assume that:

• the first is total precipitation

• the second is total snow preciptation

The fraction is calculated only on points with total precipitation >= 0.5mm

The fraction is clipped between 0 and 100.

grib_set is applied if present.

Example:

sffraction24h:
  type: sffraction
  inputs: [tpdec24h, snowdec24h]
  grib_set:
    shortName: tp

expr

given one or more source inputs, generate a new input computing its values using an expression between numpy arrays.

grib_set and clip are applied if present.

Example:

sffraction:
  type: expr
  inputs: [tpdec3h, snowdec3h]
  expr: sffraction = snowdec3h[snowdec3h != 0] * 100 / tpdec3h[snowdec3h != 0]

Reference of arguments shared by at least two input types

inputs

Lists the source inputs that are used to compute this input.

Order can matter: for example, cat will concate inputs in the order they are listed.

grib_set

In these input types, you can optionally add a grib_set dictionary argument, which is a set of key=value assignments done via eccodes on the resulting grib before writing it out.

This can be used to correct the GRIB metadata after processing.

clip

In these input types, you can optionally add a clip expression as a string.

The expression is a Python expression that can use as variables the names of the source inputs, as well as the name of the current input. The variables will be numpy arrays. The goal is to change the array named as the current input, to postprocess it before writing it out.

Example:

hzero:
 - model: ifs
   type: groundtomsl
   inputs: [z, hzeroground]
   clip: "hzero[hzero <= z] = -999"