TRANTRACE - Lists the contents of a transformation structure

Description:

This application reports or write to a text file the contents of a TRANSFORM structure. Items listed include:

• the structure's name;

• the version of the TRANSFORM software used to write the structure;

• the number of input and output variables for the nett transformation and for each transformation where the structure contains more than one;

• the classification of the forward and inverse mappings; and

• for each transformation its precision, comment, forward and inverse functions.

Usage:

trantrace transform [logfile]

Parameters:

LOGFILE = FILENAME (Write)

The name of the text file to store a list of the transformation structure. If it is null (!) the list of the transformation structure is reported directly to you. [!]

TRANSFORM = TRN (Read)

The transformation structure to be listed. This may be an HDS container file, in which case the transformation structure is assumed to be called TRANSFORM at the top level of the file; or a path to the HDS object. The suggested default is the current transformation structure.

Results Parameters:

CLASSFOR = LITERAL (Write)

A comma-separated list of classifications that describe the properties of the forward mapping of the transformation. The possible values in the list are:

"Linear" -- linear and preserves straight lines,

"Independent" -- preserves the independence of the axes,

"Diagonal" -- preserves the axes themselves,

"Isotropic" -- preserves angles and shapes,

"Positive_det" -- a component of reflection is absent,

"Negative_det" -- a component of reflection is present,

"Constant_det" -- the scale factor is constant,

"Unit_det" -- areas (or volumes etc.) are preserved.

See SUN/61 Appendix B for more details of transformation classification and a table of the classifications of common mappings.

CLASSINV = LITERAL (Write)

A comma-separated list of classifications that describe the properties of the inverse mapping of the transformation. See parameter CLASSFOR for further details.

COMMENT = LITERAL (Write)

The comment string associated with the transformation. A "-$>$" symbol, if present, indicates the forward transformation.

FORWARD = LITERAL (Write)

The expression that defines the last forward mapping of the transformation.

INVERSE = LITERAL (Write)

The expression that defines the last inverse mapping of the transformation.

PREC = LITERAL (Write)

The arithmetic precision of the transformation. This may be either "_REAL" for single precision, "_DOUBLE" for double precision, or "_INTEGER" for integer precision.

VERSION = LITERAL (Write)

The version number of the TRANSFORM software used to write the transformation structure.

Examples:

trantrace rot45.transform

This reports the contents of the transformation structure within the HDS container file rot45.sdf, component TRANSFORM.

trantrace rot45

This has the same affect as the previous example.

trantrace $\backslash$

This reports the contents of the current TRANSFORM structure.

trantrace jkt256.more.ccdpack.transform trn.lis

This lists to the text file trn.lis the contents of the transformation structure located within the HDS file jkt256.sdf, as component MORE.CCDPACK.TRANSFORM.

trantrace stretch.limit nvin=(nvi) comment=(trncom)

This reports the contents of the transformation structure within the HDS container file stretch.sdf, component LIMIT. The number of input transformation variables is written to the ICL variable called NVI, and the transformation comment is stored in ICL variable TRNCOM.

Notes:

• Where a value is not optional but is absent, "$<$undefined$>$" appears in the listing.

• TRANTRACE attempts to compile the forward and inverse mappings to check that it is a TRANSFORM structure, and will exit with an error if both of these compilations fail.

• On completion, the current transformation global parameter takes the value of parameter TRANSFORM.

Related Applications

KAPRH: TRANSFORMER, TRANINVERT, TRANJOIN, TRANMAKE; CCDPACK: CCDEDIT, TRANLIST, TRANNDF.