RIAssigner.compute.Kovats

Classes

Kovats

Class to compute the Kovats retention index.

Functions

_update_index(target_rt, reference_rts, index)	Get the indices of previosly eluting and next eluting reference compounds.
_compute_kovats(→ float)	Compute retention index according to Van den Dool (see https://webbook.nist.gov/chemistry/gc-ri/)

Module Contents

class RIAssigner.compute.Kovats.Kovats

Bases: RIAssigner.compute.ComputationMethod.ComputationMethod

Class to compute the Kovats retention index.

compute(query: RIAssigner.data.Data.Data, reference: RIAssigner.data.Data.Data) → List[RIAssigner.data.Data.Data.RetentionIndexType]

Compute non-isothermal Kovats retention index. For details see https://webbook.nist.gov/chemistry/gc-ri/.

Parameters:

• query – Dataset for which to compute retention indices.

• reference – Reference dataset with retention times and retention indices

Returns:

retention_indices – List of computed retention indices

Return type:

List[Data.RetentionIndexType]

_compute_ri(target_rt: RIAssigner.data.Data.Data.RetentionTimeType, reference_rts: Iterable[RIAssigner.data.Data.Data.RetentionTimeType], reference_ris: Iterable[RIAssigner.data.Data.Data.RetentionTimeType], index: int) → RIAssigner.data.Data.Data.RetentionIndexType

Compute retention index for target retention time.

Parameters:

• target_rt (Data.RetentionTimeType) – Retention time for which to compute the index

• reference_rts (Iterable[Data.RetentionTimeType]) – Reference retention times

• reference_ris (Iterable[Data.RetentionTimeType]) – Reference retention indices

• index (int) – Current reference index

Returns:

Computed retention index

Return type:

Data.RetentionIndexType

RIAssigner.compute.Kovats._update_index(target_rt: float, reference_rts: Iterable[RIAssigner.data.Data.Data.RetentionTimeType], index: int)

Get the indices of previosly eluting and next eluting reference compounds. Retention times in ‘Data’ objects are sorted in ascending order, so this method assumes that ‘reference_rt’ is sorted in ascending order.

Parameters:

reference_rts – Retention times of reference compounds.

RIAssigner.compute.Kovats._compute_kovats(target_rt: float, reference_rts: Iterable[RIAssigner.data.Data.Data.RetentionTimeType], reference_ris: Iterable[RIAssigner.data.Data.Data.RetentionIndexType], index: int) → float

Compute retention index according to Van den Dool (see https://webbook.nist.gov/chemistry/gc-ri/)

Parameters:

• target_rt (float) – Retention time for which to compute the RI

• reference_rts (Iterable[Data.RetentionTimeType]) – Reference data retention times

• reference_ris (Iterable[Data.RetentionIndexType]) – Reference data retention indices

• index (int) – Higher index of reference compound (n+1)

Returns:

Computed retention index

Return type:

Data.RetentionIndexType