地理信息系统开发工具GISDK使用手册英文版第四部分FunctionList教程文件.doc

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Abs()
Summary
Computes the absolute value of a number.

Syntax
rslt = Abs(real value)

Argument
Contents
value
Any number

Returns
A real number equal to the absolute value of value.

See Also
Function
Summary
Sign()
Computes the sign of a number.

Acos()
Summary
Computes the arccosine of a value.

Syntax
rslt = Acos(real value)

Argument
Contents
value
Any number between -1.0 and +1.0

Returns
A real number equal to the angle in radians whose cosine is value.

See Also
Function
Summary
Cos()
Computes the cosine of an angle expressed in radians
Asin()
Computes the arcsine of a value
Atan()
Computes the arctangent of a value

Acosh()
Summary
Computes the hyperbolic arccosine of a value.

Syntax
rslt = Acosh(real value)

Argument
Contents
value
Any number greater than or equal to 1.0

Returns
A real number equal to the number whose hyperbolic cosine is value.

Error Codes
Error Type
Meaning
Error
Value is less than 1.0

See Also
Function
Summary
Cosh()
Computes the hyberbolic cosine of an angle expressed in radians
Asinh()
Computes the hyperbolic arc sine of a value
Atanh()
Computes the hyperbolic arc tangent of a number

AddAnnotation()
Summary
Adds an annotation to a map or layout window.

Changes
From Version 3.0 added a new annotation type, splined text, which is text that follows the path of a smoothed polyline or spline curve.

Syntax
id = AddAnnotation(string window_spec, string type, array spec)

Argument
Contents
window_spec
The type and name of the window containing the annotation
type
Annotation type
spec
An array of name-value pairs that define the annotation

Annotation Type
Window Type
Valid Specifications
Bitmap
Layout, map
Color, Editable, File, Location (2 coords on a layout, a scope on a map)
Circle
Layout, map
Editable, Fill Color, Fill Style, Line Color, Line Style, Line Width, Location (a circle)
Compass
Map
Color, Editable, Font, Index, Location (a scope)
Container
Layout
Editable, Location (2 coords)
Editor
Layout
Color, Drop Shadow, Editable, Font, Grid, Line Color, Line Style, Line Width, Location (2 coords), Shadow Color, View
Ellipse
Layout, map
Angle, Editable, Fill Color, Fill Style, Line Color, Line Style, Line Width, Location (2 coords on a layout, a scope on a map)
Figure
Layout
Drop Shadow, Figure, Line Color, Line Style, Line Width, Location (2 coords), Shadow Color, Wysiwyg
Font Character
Layout, map
Angle, Color, Editable, Font, Index, Location (a coord)
Label
Map
All the options appropriate for text, plus ID, Layer
Legend
Layout, map
Editable, Location (2 coords on a layout, a scope on a map), Name
Map
Layout
Drop Shadow, Editable, Fixed Scale, Line Color, Line Style, Line Width, Location (2 coords), Map, Scope, Shadow Color, Wysiwyg
Polygon
Layout, map
Editable, Fill Color, Fill Style, Line Color, Line Style, Line Width, Points
Polyline
Layout, map
Editable, From Arrow, Line Color, Line Style, Line Width, Points, Smooth, To Arrow
Rectangle
Layout, map
Angle, Editable, Fill Color, Fill Style, Line Color, Line Style, Line Width, Location (2 coords on a layout, a scope on a map), Rounded
Splined Text
Layout, map
Editable, Points, Font, Color, Text
Text
Layout, map
Angle, Color, Editable, Font, Framed, Frame Border Color, Frame Border Style, Frame Border Width, Frame Fill Color, Frame Fill Style, Frame Shield, Frame Type, Location (2 coords on layout, a scope on map or, for non-scaling text, a coord and an alignment string on map), Text

Specification
Type
Contents
Angle
Real
The counterclockwise rotation angle from horizontal (defaults to 0)
Color
Color
The foreground color
Drop Shadow
Boolean
Indicates whether a drop shadow is displayed (defaults to false)
Editable
Boolean
Indicates whether the annotation can be edited (defaults to false)
Figure
String
The name of the figure
File
String
The path to the file containing the annotation
Fill Color
Color
The fill color
Fill Style
Fillstyle
The fill style
Fixed Scale
Boolean
Indicates whether the same map scale is used as in the original map window defaults to false)
Font
String
The name and size of the font
Framed
Boolean
Indicates whether a text item is displayed with a frame (defaults to false)
Frame Border Color
Color
The frame border color
Frame Border Style
Linestyle
The frame border style
Frame Border Width
Real
The frame border width in points
Frame Fill Color
Color
The frame background color
Frame Fill Style
Fillstyle
The frame background fill style
Frame Shield
Array
The highway shield definition (string font_name, array of (integer index, color))
Frame Type
String
Rectangle, Rounded Rectangle, Ellipse, Shield
From Arrow
Boolean
Indicates whether an arrow is drawn at the start of the polyline (defaults to false)
Grid
Boolean
Indicates whether a grid is displayed (defaults to false)
ID
Integer
ID of the feature to label
Index
Integer
The character value from the font
Layer
String

Name of the geographic layer containing the feature
Line Color
Color
The line or border color
Line Style
Linestyle
The line or border style
Line Width
Real
The line or border width in points
Location
Array
See table below
Map
String
The name of the map
Name
String
The name of the legend
Points
Array
An array of coordinates, X and Y on a layout or longitude and latitude on a map
Rounded
Boolean
Indicates whether the rectangle has rounded corners (defaults to false)
Scope
Scope
The scope of the map
Shadow Color
Color
The color of the drop shadow
Smooth
Boolean
Indicates whether the polyline is smoothed by fitting a spline (defaults to false)
Text
String
The actual text of a text annotation
To Arrow
Boolean
Indicates whether an arrow is drawn at the end of the polyline (defaults to false)
Wysiwyg
Boolean
Indicates whether the map or figure added to the layout window is sized to look identical to the original map window (defaults to true)

Location Type
Window Type
Comments
Scope
Map
A compound variable with a center, width, and height; the angle is ignored. Use Scope() or ClickRectScope() to create a scope
2 coords
Layout
Compound variables with an X and Y. Use Coord() to create a coord or ClickRect() to create a rectangle of 2 coords
A coord
Layout, map
A compound variable with an X and Y on a layout or a lon and lat on a map. Use Coord() or ClickCoord() to create a coord
A coord and an alignment string
Map
The coord is a compound variable with an X and Y on a layout or a lon and lat on a map; use Coord() to create a coord. The alignment string can be NW, N, NE, W, C, E, SW, S or SE
A circle
Layout, map
A compound variable with a radius and center. Use Circle() or ClickCircle() to create a circle

Returns
The integer id of the new annotation.

Notes
· When adding annotations to a map, Location is in longitude and latitude values.
· When adding annotations to a layout, Location is in X and Y values measured in hundredths of a printer's point (1/7200ths of an inch) from the upper-left hand corner of the layout.
· Bitmaps are scaled to fit within the Location coordinates.
· Circle annotations are converted and stored as Ellipses.
· View annotations are returned with the type Editor and their font color is returned with the Font Color specification.

Examples
id = AddAnnotation("Map|U.S. States", "Bitmap", {
{"File", "c:\\TransCAD\\bmp\\flag.bmp"},
{"Location", {ClickRectScope()}}
})

window_name = "Map|" + GetMap()
option_array = { { "Location" , Coord(750000,-430000) } ,
{ "Font" , "Caliper Cartographic|14" } ,
{ "Index" , 53 },
{ "Color" , ColorRGB(0,0,65535) } }

annotation_id = AddAnnotation(window_name,"Font Character",option_array)

Error Codes
Error Type
Meaning
NotFound
The specified window does not exist
Error
The annotation type or specification is invalid

See Also
Function
Summary
DuplicateAnnotation()
Creates a copy of an annotation
GetAnnotation()
Returns the definition of an annotation
MoveAnnotation()
Moves an annotation to a new location
SetAnnotation()
Modifies an existing annotation in a map or layout window

AddCDFLayer()
Summary
Adds a layer from a compact geographic file to a map.

Syntax
actual_lyr_name = AddCDFLayer(string map_name, string layer_name, string db_name, string db_layer_name)

Argument
Contents
map_name
The name of the map to which the image is added
layer_name
The desired name for the layer in the map
db_name
The full path and file name of the geographic file that contains the layer
db_layer_name
The layer name as defined in the geographic file

Returns
A string indicating the actual name of the layer, which is identical to layer_name unless the layer name is already in use.

Notes
· If the map_name is null, AddCDFLayer() adds the layer to the current map.
· Adding a layer to a map does not set any display characteristics for the layer. In other words, the layer is not visible until display colors and styles are assigned.
· TransCAD keeps track of geographic files and their layer names in the workspace, not just in individual map and dataview windows. The same geographic file can have the same layer name in different maps, but different geographic files cannot have the same layer name even if they are in different maps. In the latter case, TransCAD adds a colon and a sequence number to the desired layer name to make the actual layer name unique.

· AddLayer() can also be used to add compact geographic files as layers.

Example
geo_file = "h:\\data\\cccntyl.cdf"
lyrs = GetDBLayers(geo_file)
new_lyr = AddCDFLayer("United States", "Counties", geo_file, lyrs[1])

Error Codes
Error Type
Meaning
Error
The map or the specified geographic file does not exist; or
the file is not a valid geographic file; or
db_layer_name is not found in the file; or
the layer is already in the map

See Also
Function
Summary
AddLayer()
Adds a layer from a geographic file to a map
AddLayerEx()
Adds a layer from a geographic file to a map, with control of the Read Only and Exclusive modes
AddImageLayer()
Adds an image layer to a map
DropLayer()
Removes a layer from a map

AddIDField()
Summary
Adds an ID field to an existing table.

Syntax
AddIDField(string view_name, integer start, integer step, boolean indexed_flag, string newfldname, string where, array options)

Argument
Contents
view_name
The name of the view of a table; if omitted, the current table is used
start
The index of the first element; if omitted, indexing starts at 1
step
The increment to use (the default is 1)
indexed_flag
If the new ID field is to be a permanent index to the table (the default is "False")
newfldname
The proposed name of the new ID field (the default is "ID")
where
Indicates where to place the new ID field. This can be "left" or "right", meaning the field will be the leftmost or rightmost field of the table, or "auto" (the default), which means the choice of leftmost or rightmost position will be made automatically

No options are currently supported.

Returns
The actual name of the field that was added.

Notes
· If the table already has a field named newfldname, the name will be suffixed with ":1", ":2" etc., as necessary to obtain a unique field name.
· When choosing leftmost/rightmost position automatically (where="auto"), the function takes into account the type of the database, and the currently indexed fields. The choice is made in such a way as to minimize the amount of re-indexing of the original fields.
· The ID field is a long (4-byte) integer.

Example
fld_name = AddIDField("MyTable", 1000, 1, "False", "NewID", "auto", )

Error Codes
Error Type
Meaning
NotFound
No view with this name was found, or no current view was found
Error
The table cannot be modified

AddImageLayer()
Summary
Adds an image layer to a map.

Syntax
actual_lyr_name = AddImageLayer(string map_name, string layer_name, string file_name)

Argument
Contents
map_name
The name of the map to which the image is added
layer_name
The desired name for the image layer
file_name
The full path and file name of the image file

Returns
A string indicating the actual name of the layer; identical to layer_name unless the layer name is already in use.

Notes
· If the image is registered, it is displayed in its correct location.
· If the image is not already registered, AddImageLayer) automatically fits it into the map window and registers it at that location.
· TransCAD keeps track of geographic and image files and their layer names in the workspace, not just in individual map windows. The same image file can have the same layer name in different maps, but different geographic or image files cannot have the same layer name even if they are in different maps. In the latter case, TransCAD adds a colon and a sequence number to the desired layer name to make the actual layer name unique.

Example
lyr = AddImageLayer("Map of New York", "Topo Map", "j:\\nycity.tif")

Error Codes
Error Type
Meaning
Error
The image file is corrupt or in an unsupported format
NotFound
The map or the specified image file does not exist

See Also
Function
Summary
AddLayer()
Adds a layer from a standard geographic file to a map
AddLayerEx()
Adds a layer from a geographic file to a map, with control of the Read Only and Exclusive modes
AddCDFLayer()
Adds a layer from a compact format geographic file to a map
GetMapLayers()
Gets a list of the layers in a map
DropLayer()
Removes a layer from a map

AddLayer()
Summary
Adds a layer from a geographic file to a map.

Syntax
actual_lyr_name = AddLayer(string map_name, string layer_name, string db_name, string db_layer_name)

Argument
Contents
map_name
The name of the map to which the layer is added
layer_name
The desired name for the layer in the map
db_name
The full path and file name of the geographic file that contains the layer
db_layer_name
The layer name as defined in the geographic file

Returns
A string indicating the actual name of the layer, which is identical to layer_name unless the layer name is already in use.

Notes
· AddLayer() can add both standard and compact geographic files as layers.
· If the map_name is null, AddLayer() adds the layer to the current map.
· Adding a layer to a map does not set any display characteristics for the layer. In other words, the layer is not visible until display colors and styles are assigned.
· TransCAD keeps track of geographic files and their layer names in the workspace, not just in individual map and dataview windows. The same geographic file can have the same layer name in different maps, but different geographic files cannot have the same layer name even if they are in different maps. In the latter case, TransCAD