The methods that are available to users are listed below in alphabetical order along with all detail necessary to use them.
In each of these it is assumed that the mapViz object was created with the variable name mapObj. i.e.
mapObj = obj_new('mapViz')
Click on the links below to move to the desired sections.
Detail Control
Coasts
Filled Continents
Grid
Horizon
Political Boundaries
Rivers
Adding Data Layers
Lines
Points
Polygon
Trajectories
Images
Useful Public Methods
Background
Hide
Projection
Show
Adds in the coastlines
Calling Sequence
mapObj->coasts, ...keywords.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the coast icon.
COLOR
The color index of the lines being drawn.
MLINESTYLE
The line style of the boundaries being drawn. The default is solid lines. Valid linestyles are shown below:
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
MLINETHICK
The thickness of the boundary or fill lines. The default thickness is 1.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
Adds in the filled continents.
Calling Sequence
mapObj->FillContinents, ...keywords.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the filled continent icon.
COLOR
The color index of the lines being drawn.
FILL
Set this keyword to 1 to fill continent boundaries with a solid color. The color is set by the COLOR keyword. Set
this keyword to 2 to fill continent boundaries with a line fill. For line filling, the COLOR, MLINESTYLE, MLINETHICK,
ORIENTATION, and SPACING keywords can be used to control the type of line fill.
MLINESTYLE
The line style of the boundaries being drawn. The default is solid lines. Valid linestyles are shown in the table
below:
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
MLINETHICK
The thickness of the boundary or fill lines. The default thickness is 1.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
ORIENTATION
Set this keyword to the counterclockwise angle in degrees from horizontal that the line fill should be drawn. The
default is 0. This keyword only has effect if the FILL keyword is set to 2.
Adds in the grid.
Calling Sequence
mapObj->grid, ...keywords.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the grid icon.
BOX_AXES
Set this keyword to create box-style axes for map plots where the parallels intersect the sides, and the meridians
intersect the bottom and top edges of the box.
CHARSIZE
The size of the characters used for the labels. The default is 1.
CLIP_TEXT
Set this keyword to a zero value to turn off clipping of text labels.
COLOR
The color index for the grid lines.
GLINESTYLE
If set, the line style used to draw the grid of parallels and meridians. See Table 7-1, "IDL Linestyles,"
on page for a list of available linestyles. The default index is 1, drawing a dotted line.
GLINETHICK
The thickness of the grid lines. Default is 1.
LABEL
Set this keyword to label the parallels and meridians with their corresponding latitudes and longitudes. Setting
this keyword to an integer will cause every LABEL gridline to be labeled (that is, if LABEL=3 then every third
gridline will be labeled). The starting point for determining which gridlines are labeled is the minimum latitude
or longitude (-180 to 180), unless the LATS or LONS keyword is set to a single value. In this case, the starting
point is the value of LATS or LONS.
LATALIGN
This keyword controls the alignment of the text baseline for latitude labels. A value of 0.0 left justifies the
label, 1.0 right justifies it, and 0.5 centers it.
LATDEL
Set this keyword equal to the spacing (in degrees) between parallels of latitude in the grid. If this keyword is
not set, a suitable value is determined from the current map projection.
LATLAB
The longitude at which to place latitude labels. The default is the center longitude on the map.
LATNAMES
Set this keyword equal to an array specifying the names to be used for the latitude labels. By default, this array
is automatically generated in units of degrees. The LATNAMES array can be either type string or any single numeric
type, but should not be of mixed type.
When LATNAMES is specified, the LATS keyword must also be specified. The number of elements in the two arrays need
not be equal. If there are more elements in the LATNAMES array than in the LATS array, the extra LATNAMES are ignored.
If there are more elements in the LATS array than in the LATNAMES array, labels in degrees will be automatically
provided for the missing latitude labels.
The LATNAMES keyword can be also used when the LATS keyword is set to a single value. It this case, the first label
supplied will be used at the specified latitude; subsequent names will be placed at the next latitude line to the
north, wrapping around the globe if appropriate. Caution should be used when using LATNAMES in conjunction with
a single LATS value, since the number of visible latitude gridlines is dependent on many factors.
LATS
Set this keyword equal to a one or more element vector of latitudes for which lines will be drawn (and optionally
labeled). If LATS is omitted, appropriate latitudes will be generated based on the value of the (optional) LATDEL
keyword. If LATS is set to a single value, that latitude and a series of automatically generated latitudes will
be drawn (and optionally labeled). Automatically generated latitudes have the values:
[...,LATS-LATDEL,LATS,LATS+LATDEL,...]
over the extent of the map. If LATS is a single value, that value is taken to be the starting point for labelling
(See the LABEL keyword).
LONALIGN
This keyword controls the alignment of the text baseline for longitude labels. A value of 0.0 left justifies the
label, 1.0 right justifies it, and 0.5 centers it.
LONDEL
Set this keyword equal to the spacing (in degrees) between meridians of longitude in the grid. If this keyword
is not set, a suitable value is determined from the current map projection.
LONLAB
The latitude at which to place longitude labels. The default is the center latitude on the map.
LONNAMES
Set this keyword equal to an array specifying the names to be used for the longitude labels. By default, this array
is automatically generated in units of degrees. The LONNAMES array can be either type string or any single numeric
type, but should not be of mixed type.
When LONNAMES is specified, the LONS keyword must also be specified. The number of elements in the two arrays need
not be equal. If there are more elements in the LONNAMES array than in the LONS array, the extra LONNAMES are ignored.
If there are more elements in the LONS array than in the LONNAMES array, labels in degrees will be automatically
provided for the missing longitude labels.
The LONNAMES keyword can be also used when the LONS keyword is set to a single value. It this case, the first label
supplied will be used at the specified longitude; subsequent names will be placed at the next longitude line to
the east, wrapping around the globe if appropriate. Caution should be used when using LONNAMES in conjunction with
a single LONS value, since the number of visible longitude gridlines is dependent on many factors.
LONS
Set this keyword equal to a one or more element vector of longitudes for which lines will be drawn (and optionally
labeled). If LONS is omitted, appropriate longitudes will be generated based on the value of the (optional) LONDEL
keyword. If LONS is set to a single value, that longitudes and a series of automatically generated longitudes will
be drawn (and optionally labeled). Automatically generated longitudes have the values:
[...,LONS-LONDEL,LONS,LONS+LONDEL,...]
over the extent of the map. If LONS is a single value, that value is taken to be the starting point for labelling
(See the LABEL keyword).
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
ORIENTATION
Set this keyword equal to an angle in degrees from horizontal (in the clockwise direction) to rotate the labels.
Adds in the horizon.
Calling Sequence
mapObj->horizon, ...keywords.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the horizon icon.
FILL
Set this keyword to 1 to fill the horizon boundaries with a solid color. The color is set by the COLOR keyword.
Set this keyword to 2 to fill horizon boundaries with a line fill. For line filling, the COLOR, MLINESTYLE, MLINETHICK,
ORIENTATION, and SPACING keywords can be used to control the type of line fill.
MLINESTYLE
The line style of the horizon fill being drawn. The default is solid lines. Valid linestyles are shown in the table
below:
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
MLINETHICK
The thickness of the horizon fill lines. The default thickness is 1.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown
Adds in the political boundaries.
Calling Sequence
mapObj->politicalBoundaries, ...keywords.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the political boundaries icon.
COLOR
The color index of the lines being drawn.
MLINESTYLE
The line style of the boundaries being drawn. The default is solid lines. Valid linestyles are shown below:
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
MLINETHICK
The thickness of the boundary or fill lines. The default thickness is 1.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
Adds in the rivers.
Calling Sequence
mapObj->rivers, ...keywords.
lonVariable and latVariable must be in degrees east.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the rivers icon.
COLOR
The color index of the lines being drawn.
MLINESTYLE
The line style of the rivers being drawn. The default is solid lines. Valid linestyles are shown below:
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
MLINETHICK
The thickness of the rivers lines. The default thickness is 1.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
Adds in data to be displayed as a line.
Calling Sequence
mapObj->add,lonVariable,latVariable,displayType='line', ...keywords.
lonVariable and latVariable must be in degrees east.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
PSYM
The symbol used to mark each data point. Normally, PSYM is 0, data points are connected by lines, and no symbols
are drawn to mark the points. Set this keywordto the symbol index as shown in the table below to mark data points
with symbols. The keyword SYMSIZE is used to set the size of the symbols.
PSYM Value Plotting Symbol
1 Plus sign (+)
2 Asterisk (*)
3 Period (.)
4 Diamond
5 Triangle
6 Square
7 X
SYMSIZE
Specifies the size of the symbols drawn when PSYM is set. The default size of 1.0 produces symbols approximately
the same size as a character.
THICK
This keyword controls the thickness of the lines forming the axis and tick marks. A value of 1.0 is the default.
Adds in data to be displayed as a point or points.
Calling Sequence
mapObj->add,lonVariable,latVariable,displayType='point' ...keywords.
lonVariable and latVariable may be either a scalar or an array in degrees east.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LABEL
Scalar or array of strings that will label the input points.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
PSYM
The symbol used to mark each data point. Normally, PSYM is 0, data points are connected by lines, and no symbols
are drawn to mark the points. Set this keywordto the symbol index as shown in the table below to mark data points
with symbols. The keyword SYMSIZE is used to set the size of the symbols.
PSYM Value Plotting Symbol
1 Plus sign (+)
2 Asterisk (*)
3 Period (.)
4 Diamond
5 Triangle
6 Square
7 X
SYMSIZE
Specifies the size of the symbols drawn when PSYM is set. The default size of 1.0 produces symbols approximately
the same size as a character.
THICK
This keyword controls the thickness of the lines forming the axis and tick marks. A value of 1.0 is the default.
Adds in data to be displayed as a polygon.
Calling Sequence
mapObj->add,lonVariable,latVariable,displayType='polygon' ...keywords.
lonVariable and latVariable must be an array with values in degrees east.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
ORIENTATION
Set this keyword equal to an angle in degrees from horizontal (in the clockwise direction) to rotate the labels.
Adds in data to be displayed as a trajectory. A trajectory can be any data set with longitude, latitude, and altitude values.
Calling Sequence
mapObj->add,lonVariable,latVariable,altitudeVariable, displayType='trajectory', ...keywords
lonVariable and latVariable must be in degrees east. The altitude Variable must be in earth radii.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
PSYM
The symbol used to mark each data point. Normally, PSYM is 0, data points are connected by lines, and no symbols
are drawn to mark the points. Set this keywordto the symbol index as shown in the table below to mark data points
with symbols. The keyword SYMSIZE is used to set the size of the symbols.
PSYM Value Plotting Symbol
1 Plus sign (+)
2 Asterisk (*)
3 Period (.)
4 Diamond
5 Triangle
6 Square
7 X
SYMSIZE
Specifies the size of the symbols drawn when PSYM is set. The default size of 1.0 produces symbols approximately
the same size as a character.
THICK
This keyword controls the thickness of the lines forming the axis and tick marks. A value of 1.0 is the default.
Adds in data to be displayed as an image.
Calling Sequence
mapObj->add,image, displayType='image', ...keywords
Keywords - These keywords may also be controlled through the layer manager by double clicking on the image icon.
LATMIN
The latitude corresponding to the first row of Image. The default is -90 degrees. Note also that -90° £
LATMIN < LATMAX £ 90°.
LATMAX
The latitude corresponding to the last row of Image. The default value is 90 degrees. Note also that -90° £
LATMIN < LATMAX £ 90°.
LONMIN
The longitude corresponding to the first (leftmost) column of the Image argument. Select LONMIN so that -180°
£ LONMIN £ 180°. The default value is -180.
LONMAX
The longitude corresponding to the last (rightmost) column of the Image argument. Select LONMAX so that it is larger
than LONMIN. If the longitude of the last column is equal to (LONMIN - (360. /Nx)) MODULO 360, it is assumed that
the image covers all longitudes (Nx being the total number of columns in the Image argument).
BILINEAR
Set this flag to use bilinear interpolation to soften edges in the returned image, otherwise, nearest neighbor
sampling is used.
COMPRESS
This keyword, the interpolation compression flag, controls the accuracy of the results from MAP_IMAGE. The default
is 4 for output devices with fixed pixel sizes. The inverse projection transformation is applied to each ith row
and column. Setting this keyword to a higher number saves time while lower numbers produce more accurate results.
Setting this keyword to 1 solves the inverse map transformation for every pixel of the output image.
SCALE
Set this keyword to the pixel/graphics scale factor for devices with scalable pixels (e.g., PostScript). The default
is 0.02 pixels/graphic coordinate. This setting yields an approximate output image size of 350 x 250. Make this
number larger for more resolution (and larger PostScript files and images), or smaller for faster, smaller, and
less accurate images.
MAX_VALUE
Data points with values equal to or greater than this value will be treated as missing data, and will be set to
the value specified by the MISSING keyword.
MIN_VALUE
Data points with values equal to or less than this value will be treated as missing data, and will be set to the
value specified by the MISSING keyword.
MISSING
The pixel value to set areas outside the valid map coordinates. If this keyword is omitted, areas outside the map
are set to 255 (white) if the current graphics device is PostScript, otherwise they are set to 0.
Sets a new projection.
Calling Sequence
mapObj->projection, ...keywords
Keywords
PROJECTION
Any of the valid types.
'cylindrical'
'mercator'
'miller cylindrical'
'mollweide'
'hammer aitoff'
'orthographic'
'perspective'
MAKEBUTTONSENSITIVE
Setting this keyword will make the button with projection name insensitive.
Makes the map invisible.
Calling Sequence
mapObj->hide
Keywords
NONE
Makes the map visible.
Calling Sequence
mapObj->show
Keywords
NONE
Changes the map background.
Calling Sequence
mapObj->background, color=color
Keywords
COLOR
The color index of the new background.