Abstract Class Name: Axis
Subclasses
Definition
A set of values of an independent variable used to organize the dependent
values in a Data Table.
Primary Page in DRM Diagram:
Example
- A table of Digital Terrain Elevation Data (DTED) contains terrain
elevation data sampled in a grid of regularly spaced longitude and
latitude points. The Axes of such a table would be
longitude and latitude.
- A table of ocean temperature and salinity data taken at varying depths
by an expendable bathythermograph can be captured in a table. Such a
table would have depth as an axis, and temperature and pressure would be
Table Property Descriptions.
If these data were taken at intervals along a path, the locations on
that path (say longitudes) would form a second Axis
of the now two-dimensional table.
FAQs
- How are the values on an Axis related?
- The values on a single Axis must be distinct values
of a single variable specified by the axis_type EAC. If the axis is numeric,
then the values must be arranged monotonically.
- Can an Axis have no values or a single
value?
- An Axis must have at least one value; an axis with
no values is a violation of SEDRIS' business rules. If the
Axis has a single value, this implies that all of the
data in the table shares that value. There may be better ways to associate
a single value with all the table entries.
- I have 2 variables, but certain combinations of values for these
2 variables are impossible or meaningless. Can I combine these 2
variables on a single Axis in order to exclude the
meaningless cells?
- No. You should include the meaningless cells, and set a value for
SE_POINT_EXCLUDED, and use it for those cells.
Constraints
None.
Component of (one-way)
Notes
Fields Notes
gives the type of measurement along the axis, such as distance,
pressure, frequency, etc.
specifies the unit of measurement of the axis_type
indicates the number of "hash marks" along the axis
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