improver.wxcode.wxcode_decision_tree module

Module containing weather symbol decision tree

improver.wxcode.wxcode_decision_tree.wxcode_decision_tree()

Define queries that comprise the weather symbol decision tree. Each queries contains the following elements:

• succeed: The next query to call if the diagnostic being queried

  satisfies the current query.

• fail: The next query to call if the diagnostic being queried

  does not satisfy the current query.

• probability_thresholds: A list of probability thresholds that the

  query requires. One entry is provided for each diagnostic field being tested.

• threshold_condition: The condition the diagnostic must satisfy

  relative to the probability threshold (e.g. greater than (>) the probability threshold).

• condition_combination: The way (AND, OR) in which multiple

  conditions should be combined; e.g. rainfall > 0.5 AND snowfall > 0.5

• diagnostics_fields: The diagnostics which are being used in the

  query. If this is a list of lists, the two fields in a given list are subtracted (1st - (2nd * gamma)) and then compared with the probability threshold.

• diagnostic_gamma (NOT UNIVERSAL): This is the gamma factor that

  is used when comparing two fields directly, rather than comparing a single field to a probability threshold. e.g. gamma * P(SnowfallRate) < P(RainfallRate).

• diagnostic_thresholds: The thresholding that is expected to have

  been applied to the input data; this is used to extract the approproate data from the input cubes.

• diagnostic_conditions: The condition that is expected to have

  been applied to the input data; this can be used to ensure the thresholding is as expected.

Returns:A dictionary containing the queries that comprise the decision tree. Return type:queries (dict)