Filling Out the Spectral Library Dictionary Classes

The spectral library dictionary is a discipline dictionary, which means that its classes will appear in the <Discipline_Area> at the bottom of the <Observation_Area> in observational product labels (and in the <Context_Area>, if appropriate, in non-observational products). The classes in this dictionary are used for spectral data products that result from laboratory observations. They are used to define the characteristics of the sample involved and the measurements made.

The reserved abbreviation for use with this dictionary is "speclib".

Last update: 17 August 2017, begin creation.

The Spectral Library Dictionary has an optional wrapper class which can be used to contain the four major subclasses, or each of the subclasses can be used individually in the <Discipline> area.

<Spectral_Library_Product>

OPTIONAL

This is the optional wrapper class. If you use it, then it will include at least three of the following entry classes as indicated and in the following order:

1. <Specimen_Parameters> must be present exactly once;
2. <Specimen_Classification> must be present exactly once;
3. <Measurement_Parameters> must be present at least once and may be repeated as desired; and
4. <Ancillary_Products> is optional, and may also be repeated as desired.

<Specimen_Parameters>

OPTIONAL

This class describes the specimen that was the target of the spectrum. If used outside of the Spectral_Library_Product wrapper class, it may be repeated.

<specimen_id>

REQUIRED

A unique identifier for the specimen.

Note: The context for "unique" is not defined.

<specimen_name>

OPTIONAL

This is the name by which the specimen is known to the specimen curator.

Note: This is a guess - it is possible that specimen_name is the local name while specimen_id is the curator's identifier.

<specimen_description>

OPTIONAL

A short (300 ASCII characters or less), prose description of the specimen.

<source_specimen_id>

OPTIONAL

This is the identifier for a larger specimen from which the present specimen was derived.

It's not clear whether this "id" correlates in any way with either specimen_id or specimen_name. This attribute is both optional and nillable, which is not in keeping with the PDS4 IM best practices.

<specimen_min_size>

REQUIRED

This attribute provides the minimum particle size comprising the sample. You must provide the appropriate units of length for this attribute. For example:

<specimen_min_size unit="mm">0.1</specimen_min_size>

NOTE: This is a guess. I don't understand this attribute and the one following.

<specimen_max_size>

REQUIRED

This attribute provides the maximum particle size comprising the sample. You must provide the appropriate units of length for this attribute.

<specimen_collection_location>

REQUIRED

This is the place where the specimen was collected.

While this attribute is required, it is not nillable. Rather, then dictionary instructs users to put a value of "Unknown" in the keyword. This is also not in keeping with PDS4 IM best practices, and present some issues for validation. It is not clear if this refers to the specimen observed or the source specimen, when one exists.

<specimen_owner_location>

REQUIRED

This actually provides the name of a facility or other location where the specimen is permanently curated. If not known, this attribute can be defined as "nil" with a reason of "unknown", thus:

<specimen_owner_location xsi:nil="true" nilReason="unknown"/>

It is not clear if this refers to the specimen observed or the source specimen, when one exists.

<specimen_owner_name>

REQUIRED

The name of a facility or other location that "owns" the specimen. This attribute may be set to nil with an appropriate reason if needed.

It is not clear if this refers to the specimen observed or the source specimen, when one exists.

<Specimen_Classification>

OPTIONAL

This class provides a list of geological characteristics for classifying the specimen observed.