Advanced or Seldom Used #Units Parameters

CASE = Upper / Lower / Mixed

Case conversion is applied to station names if you use CASE=L (convert to lower case) or CASE=U (convert to upper case).  CASE=M is the default setting which insures that the case actually appearing in names is significant.  This parameter has no affect on station name prefixes, where case is always significant.  It also doesn't apply to notes and segment names.

LRUD = F / T / FB / TB

LRUD = <type>:<order>

Four popular LRUD style options are currently supported: FROM-station-perpendicular, TO-station-perpendicular, FROM-station-bisector, and TO-station-bisector. The default style is FROM-station-perpendicular, where the dimensions appearing on a vector's data line are taken at that same vector's FROM station and describe a passage cross-section that's perpendicular to the vector's horizontal component. If there is no horizontal component, the program attempts to find one in the previous or next shot. The bisector styles produce cross-sections that bisect the angle between adjacent vectors.

An example of the second form of the assignment is LRUD=T:UDLR.  This specifies TO-station LRUDs with the ceiling and floor distances appearing before the left and right wall distances. Thus the order that dimension types appear in the data can be specified. The default assumption is LRUD=F:LRUD. (Note the colon delimiter with no space on either side.)

For much more information about LRUDs, see LRUD Passage Dimensions under Vector Data Lines.

PREFIX=<name>

PREFIX2=<name2>

PREFIX3=<name3>

This option sets the current station name prefix of a particular level, with up to three levels being supported. When the keyword appears without an assigned name, the prefix for that level is cleared.  The #Prefix Directive is normally the preferred method of prefix assignment, but this parameter form allows default prefixes to be set for entire project tree branches via the "Compile Options" field in the Properties dialog.  The compile options field only accepts #Units arguments.

TAPE = IT / SS / IS / ST

For the sake of completeness (and to make importing data from other programs simpler), Walls now supports the four different "taping methods": Instrument-to-Target, Station-to-Station, Instrument-to-Station, and Station-to-Target.  The default method is Instrument-to-Target (IT), which is also the recommended method for anything but underwater surveys.  The taping method comes into play only for compass and tape (CT) vectors where instrument/target heights above station have been recorded.  The instrument of relevance here, of course, is the clinometer, not the compass.  For further discussion of this feature, see the section on IT heights under Vector Data Lines.

UVH / UVV / UV = <nonnegative number>

The assumed variances of all vectors, whether they be compass and tape (CT), rectangular (RECT), or the hidden vectors of #FIX directives, will be multiplied by this number, a "unit variance" scaling factor.  Use the keyword UVH, UVV, or UV to indicate whether the variances of horizontal components, vertical components, or both types of vector component are to be affected.

Note that these settings will be applied to all (non-floated) vectors, including those whose default variances have been overridden (see Variance Assignments).  The default setting is UV=1.0.

You will not normally want to use this feature since values other than 1.0, if applied to an entire survey, will affect only the UVEs, while F-ratios and coordinate estimates remain unchanged.  You can verify, for example, that setting UVH or UVV to the corresponding UVE resulting from a default compilation will produce a new UVE of 1.0.

However, on occasion you may want to treat certain surveys, or portions of surveys, as being more reliable than others -- at least in the final adjustment.  For example, assigning UV=0.01 to a set of vectors would cause them to be treated in the adjustment as if their error components had one hundredth their normal variance (or one tenth their normal standard deviation).

You may use "UV=0", for example, to constrain a set of vectors -- a shortcut to placing the variance override "(0)" on each data line.  However, if you do this, be careful that there exist no loops consisting entirely of constrained vectors, which will cause Walls to abort the adjustment with a message indicating the presence of fundamentally inconsistent data.  (This will occur even if you try to insure that the closure distance is zero.)  The work around is to use the override "(?)" to float any such vectors that form closures.

FLAG = "flag name"

FLAG

This option sets the current default flag name for #FIXed stations, or removes it when the keyword appears without an assigned value.  Note that quotes are necessary when the flag name has embedded white space.  The #Flag directive is normally the preferred method of flag assignment, but this parameter form allows the default flag to be set for entire project tree branches via the Compile Options property dialog.  The text box in that dialog only accepts #Units arguments.

$<name> = <"replacement string">

$<name>

Any name of your choosing prefixed with a dollar sign is treated as a macro name. It's definition, or replacement string, is the string of characters to the right of the equals sign -- a string that  must be quoted if it contains spaces or commas. When there is no equals sign, the replacement string is taken to be the empty, zero-length string. During compilation, the program examines all directive lines (excluding  #FIX directives) for macro references, then replaces those it finds with the corresponding replacement strings. It does this before the directive line is processed in the normal fashion. Macro references have the form $(name) and can be used to construct any portion of a directive line following the hash-prefixed directive name. For more details and examples see Defining and Using Macros.