# presentations/2012-HPDE-Feb-SPASE

SPASE Numerical Data use cases

# 1. Overview

• We need a clear vision for the intended use of SPASE Numerical Data records.
• I was not able to use them when creating catalog-level metadata for TSDS and so I wondered what they are meant to be used for.
• I came up with four possibilities inferred by inspection of a few records.
• As implemented, the SPASE Numerical Data records are not good at any of the four possibilities.
• We need to decide on the use-case for these SPASE records. Without agreement, they will not be useful for any of the four purposes. Some of the use-cases require a significant time investment for generation and maintenance. This should be considered.
• Before making a push for "completeness" of the Numerical Data SPASE record inventory, we need to decide if the completed inventory will be useful for at least one use-case.

# 2. Outline

Inspection of SPASE Numerical Data records indicates that it could be intended for use for:

1. To inform the user where data are available from. (A science use-case.)
2. As a replacement for a README. (A science use-case.)
3. For automated machine processing of ASCII files. (An automation use-case.)
4. For connecting a parameter ID from one system to another system. (An automation use-case.)

We need to decide on the use-case for these SPASE records so that they are useful for at least one thing.

In the following I justify my claim that existing SPASE records are not very useful for any of these four use cases.

# 3. Use 1.

1. To inform the user where these data are available from.

Consider this search on "OMNI2" [1], results of which are shown in the image.

 Issues: The link SPDF CDF ftp area data is to files that have only a few parameters listed in the SPASE record - what does this mean? As a science user presented with this, I ask: Why are these data are located at five different places? Will I get identical data from each URL? If yes, why do we need five choices? If they are not identical, which one should I use? Which SPASE ID is associated with the data from each resource?

# 6. Use 2.

2. As a replacement to a README.

• If yes, then lots of information in the original README has been lost (c.f., [4] versus [5] or [6]) is the README author OK with this?
• Why doesn't the SPASE record provide a direct link to the definitive "master" documentation? (A science user may not want to visit five links to make sure that they have found all of the documentation.)

# 7. Use 3.

3. For automated machine processing of the ASCII files.

• This OMNI2 SPASE record [7] notes that the cadence of the ap Index is PT3H. But in the OMNI2 files, the cadence is PT1H.

This would confuse an automated processor.

Parameter:
Name: ap Index
ParameterKey: Column 50
Description: ap index
Support:
SupportQuantity: Other


# 8. Use 4.

4. For connecting a parameter ID from one system to another system.

Issues:

• To make TSDS work, I need a parameter ID so that I can form a data request to CDAWeb. CDAWeb's web service uses IDs that are quite different than what is found in a typical SPASE record: [8]
• This SPASE record [9] seems to point to the same data product as [10]. Which one should I use?

# 9. Use 4. continued

• The 5th result of a search on "ap index" at VSPO points me to this (broken) link: [11]
• CDAWeb has a variable named PC_N_INDEX1800 in its master catalog. What does 1800 mean? How am I to figure out that this is the same parameter as listed in the OMNI2 SPASE record, which contains:
Parameter:
Name: Polar Cap (N) Index
ParameterKey: Column 52
Description: Polar Cap Index based on Thule