Chapter 4. Sample Visual Programs and Sample Macros

The directory /usr/local/dx/samples/programs contains a number of sample visual programs. In addition, a set of subdirectories categorize programs by subject (e.g., 2-D Data, Annotation, etc.). To start, you may want to look at the programs in the subdirectory /SIMPLE.

The sample visual programs listed here can be invoked, like any visual program, from the VPE. To access the available sample programs, enter: /usr/local/dx/samples/programs/*.net in the Filter field (of the Open... dialog box) and press Enter.

The macro descriptions are in 4.2 , "Sample Macros".

Notes:

1. For the user's convenience, and where appropriate, some programs have been listed in more than one section.
2. Once a program has been opened, relevant descriptive and tutorial information can be accessed with:
   • the Application Comment option of the Help pull-down menu (in either the Image window or the VPE window)
   • the Open dialog box, by clicking on the Comments button.

4.1 Sample Visual Programs

Simple Visual Programs

Found in directory $DXROOT/samples/programs/SIMPLE

Each example program listed here illustrates a typical use of the Data Explorer module it is named for.

Arrange.net
AutoAxes.net
AutoColor.net
AutoGlyph.net
AutoGrid.net

Band.net
Caption.net
Color.net
ColorBar.net
Compute2.net
Connect.net

Construct.net
Describe.net

FaceNormals.net
GetSet.net
Gradient.net
Grid.net
Histogram.net
Include.net
Isolate.net

Isosurface.net
Light.net
Map.net

MapToPlane.net
MarkUnmark.net
Post.net
QuantizeImage.net

Reduce.net
Refine.net
Regrid.net

Route.net
Rubbersheet.net
ScaleScreen.net

ShowBoundary.net
Slab.net
Sort.net

Streamline.net
Supervise.net
Switch.net

Verify.net
VisualObject.net

2-Dimensional Data

Found in directory $DXROOT/samples/programs/2D_DATA

AlternateVisualizations.net Various ways to visualize 2-dimensional data sets.

BandedColors.net How to create an image with a set of constant-color bands

ConnectingScatteredPoints.net How to use the Connect and Regrid modules to create connections (interpolation elements) between points.

FFT.net Computing fast and discrete Fourier transformations on sample data sets.

GeneralImport1.net, GeneralImport2.net Importing data in the general array import format.

InvalidData.net How data marked as invalid are handled by various modules.

Sealevel.net Visualizing the effect of rising sea levels on eastern U.S. coastlines.

Sort.net How to sort a field based on the y-position.

Topo.net Some ways of visualizing topographic data (in this example, two data sets sharing the same grid: elevation and a gray-scale image).

UsingDrape.net How to "drape" an image or other field onto a height map.

UsingFilter.net How to perform filtering operations on images.

UsingIsosurface.net How to create isosurfaces and contour lines.

UsingMorph.net How to perform morphological operations on images.

UsingOverlay.net Using the Overlay module to combine images.

3-Dimensional Data

Found in directory $DXROOT/samples/programs/3D_DATA

AnnotationGlyphs.net How to create your own glyphs for use with AutoGlyph and Glyph.

AutoColor.net A simple use of AutoColor to color a 3D field.

CappedIso.net How to "close" an isosurface at the boundary of a three-dimensional volume.

ComputeOnData.net How to perform a mathematical function on all the data values in a field.

ContoursAndCaption.net How to draw contour lines on a plane. The position of the plane is controlled by the Sequencer, and a caption shows the current position of the plane.

Distributed.net Demonstrating the module-level distributed processing capabilities of Data Explorer. The network is decomposed into three mutually disjoint subsets, each of which can be executed on a different host in a distributed network.

FlyThrough.net, FlyThrough2.net Two ways to create a "fly through" of data.

Imide_Potential.net Visualizing a molecule in a potential field. This program also demonstrates the use of a data-driven sequencer.

Isolate.net How to isolate connections of an object.

MappedIso.net How to map a variable onto an isosurface of another variable.

MovingCamera.net Using the Sequencer to control the position of the viewing point.

MovingSheet.net Using the Sequencer to control the position of a slice through a data set.

MRI_2.net One way to visualize a set of 2-dimensional MRI slices as a 3-dimensional volume.

PickStreamline.net Using the Pick tool to select points (on an isosurface) as the origin of streamlines in the data.

PlotLine.net, PlotLine2.net, PlotTwoLines.net Using the Plot module to display 2-dimensional plots of data values.

ProbeText.net One way to place text in an image to show data values at probe points.

RubberTube.net How to make a tube diameter vary with the data value.

SharedCamera.net How to create two images that share the same camera. One of the images is used for rotating, zooming, and resizing; the other tracks the changes.

SimplifySurface.net How to simplify a surface consisting of triangles so that fewer triangles are used.

Streamline.net Using parameters of the Streamline module to visualize a vector field.

ThunderGlyphSheet.net Visualization of simulation data from a model of a thunder storm. (A slicing surface of variable position and shape is used to intersect an isosurface of the data; the area of the isosurface is calculated and displayed.)

ThunderStreamlines.net Using the Streamline module to visualize a wind field.

Thunder_cellcentered.net Differences between position-dependent and connection-dependent (cell-centered) data.

UsingClipPlane.net Using probes to control the orientation of the clipping plane.

UsingGlyphs.net Using the AutoGlyph module to create glyphs for data values.

UsingIsosurface How to create isosurfaces and contour lines.

UsingMap.net Three ways to use the Map module. Two fields differing only in the content of their data components are used as the data-set and mapping operands of the Map module. The results are displayed in three separate windows.

UsingStreakline.net Using the Streakline module to visualize a vector-field series.

VolumeClip.net How to clip a surface in a three-dimensional volume by a plane and then close the surface by the plane.

VolumeRenderingSimple.net, VolumeRendering.net How to create a volume rendering of a 3-dimensional data set. The first example is the simplest possible visual program; the second is more complex, with a color bar to annotate the image.

WindVorticity.net Using the DivCurl module to display the vorticity of a vector field. The program also uses a shared camera and data-driven interactors.

Annotation

Found in directory $DXROOT/samples/programs/ANNOTATION

AnnotationGlyphs.net How to create your own glyphs for use with AutoGlyph and Glyph.

AutoAxesSpecifyTicks.net How to explicitly specify tick locations and labels for the ticks.

BandedColors.net How to create an image with a set of constant color bands.

Categorical.net How to display categorical (non-spatial) data

ContoursAndCaption.net How to draw contour lines on a plane. The position of the plane is controlled by the Sequencer, and a caption shows the current position of the plane.

Distributed.net Demonstrating the module-level distributed processing capabilities of Data Explorer. The network is decomposed into three mutually disjoint subsets, each of which can be executed on a different host in a distributed network.

ExpandedFonts.net How to use the expanded font sets of the area and roman_ext fonts.

FontPreview.net Displaying ASCII text in a Data Explorer font.

GroceryList.net Plots information from a grocery list in a number of different ways; by category, by item name, etc.

Imide_Potential.net Visualizing a molecule in a potential field. This program also demonstrates the use of a data-driven sequencer.

Legend.net Shows how to use the Legend module to associate colors with strings.

PickPlot.net Demonstrates how to use picking in a plot to extract x,y positions.

PlotGroupOfLines.net How to plot a multiple-line graph

PlotLine.net, PlotLine2.net, PlotTwoLines.net Using the Plot module to display 2-dimensional plots of data values.

PlotSpecifyTicks.net How to explicitly specify tick locations and labels.

ProbeText.net One way to place text in an image to show data values at probe points.

SalesOnStates.net Shows how to display sales or other data on a per-state basis.

Sort.net How to sort a field based on the y-position.

SpecialCharacters.net Displaying all of the characters in the "pitman" or "area" fonts supplied with Data Explorer. How to specify non-ASCII characters.

ThunderGlyphSheet.net Visualization of simulation data from a model of a thunder storm. (A slicing surface of variable position and shape is used to intersect an isosurface of the data; the area of the isosurface is calculated and displayed.)

UsingGlyphs.net Using the AutoGlyph module to create glyphs for data values.

UsingTextAndTextGlyphs.net How to display text data at specified locations in the space occupied by an object.

Categorical

Found in directory $DXROOT/samples/programs/CATEGORICAL

Categorical.net How to display categorical (non-spatial) data

Duplicates.net How to detect duplicate values in a data set using CategoryStatistics

GroceryList.net Plots information from a grocery list in a number of different ways; by category, by item name, etc.

Legend.net How to create a legend, which associates a set of colors with a set of strings

SalesOnStates.net How to display sales data by state

ZipCodes.net How to import some data associated with zipcodes using ImportSpreadsheet, then display those data on a state map. This program also illustrates the use of CategoryStatistics to compute the mean data value for each category (in this case, zipcode).

Colormap Editor

Found in directory $DXROOT/samples/programs/COLORMAP_EDITOR

DataDrivenInteractors.net Some uses of data-driven interactors.

Imide_Potential.net Visualizing a molecule in a potential field. This program also demonstrates the use of a data-driven Sequencer.

StandardColormaps Demonstrates a number of useful colormaps, depending on the type of data being viewed.

UsingColorMaps.net Using color maps to control the visualization of data.

VolumeRendering.net How to create a volume rendering of a 3-dimensional data set.

Compute

Found in directory $DXROOT/samples/programs/COMPUTE

(Compute is a general purpose module for performing mathematical operations on data.)

Bounce.net The path of a bouncing ball.

Compute2.net A simple visual program which demonstrates how to use the Compute2 module.

ComputeMultiLine.net How to pass a multiline arithmetic expression to Compute2.

ComputeOnData.net How to perform a mathematical function on all the data values in a field.

WarpingPositions.net How to use the Compute module to "warp" the positions component of a field (e.g., warping a 2-dimensional field into the shape of a cylinder or sphere).

Data-driven Interactors

Found in directory $DXROOT/samples/programs/DATA_DRIVEN_INTERACTORS

DataDrivenInteractors.net Some uses of data-driven interactors.

DataDrivenSelector.net How to use a data-driven selector interactor.

Imide_Potential.net Visualizing a molecule in a potential field. This program also demonstrates the use of a data-driven Sequencer.

Debugging

Found in directory $DXROOT/samples/programs/DEBUGGING

Verify.net How to check the internal consistency of a data object.

VisualObject.net Display the hierarchy of a data field.

Distributed Processing

Found in directory $DXROOT/samples/programs/DISTRIBUTED_PROCESSING

Distributed.net Demonstrating the module-level distributed processing capabilities of Data Explorer. The network is decomposed into three mutually disjoint subsets, each of which can be executed on a different host in a distributed network.

Image Processing

Found in directory $DXROOT/samples/programs/IMAGE_PROCESSING

FFT.net Computing fast and discrete Fourier transformations on sample data sets.

MRI_1.net One way to visualize 2-dimensional MRI slices.

UsingEqualize.net How to use the Equalize module to emphasize features in an image.

UsingFilter.net How to perform filtering operations on images.

UsingMorph.net How to perform morphological operations on images.

UsingOverlay.net Using the Overlay module to combine images.

Importing Data

Found in directory $DXROOT/samples/programs/IMPORTING

Categorical.net How to import some data associated with state abbreviations using ImportSpreadsheet, then plot the average data for each state.

Duplicates.net checks a simple table of data and checks for duplicate state names.

GeneralImport1.net, GeneralImport2.net Importing data in the general array import format.

ImportExternalFilter.net How to use the external-filter option of the Import module to import data in file formats other than Data Explorer.

ZipCodes.net How to import some data associated with zipcodes using ImportSpreadsheet, then display those data on a state map. This program also illustrates the use of CategoryStatistics to compute the mean data value for each category (in this case, zipcode).

Interface Control

Found in directory $DXROOT/samples/programs/INTERFACE_CONTROL

DialogStyle.net Using dialog-style control panels. This program is intended to run with Data Explorer in image mode (i.e., started with dx -image).

InterfaceControl1.net Using ManageControlPanel and ManageColormapEditor to open and close control panels and the Colormap editor according to the setting of the Selector interactor (alternating between two realization techniques).

InterfaceControl2.net Using ManageImageWindow to close a plot image window when a toggle interactor requires it.

InterfaceControl3.net Using ManageControlPanel to open and close different multiple panels.

Looping

Found in directory $DXROOT/samples/programs/LOOPING

Accumulate.net How to use Get and Set to accumulate objects (in this case, slabs selected from a 3-dimensional volume).

Bounce.net The path of a bouncing ball.

SimpleGetSetLoop.net How to create a program loop with GetLocal/SetLocal, GetGlobal/SetGlobal, and Done.

Miscellaneous

Found in directory $DXROOT/samples/programs/MISC

CensusData.net How to visualize census data on a map of the United States.

ExampleSMP.net How Partition should be incorporated in a visual program so that Data Explorer SMP can run it in parallel on SMP (symmetric multiprocessor) machines.

Factorial.net How to compute N factorial using looping.

HomeOwn.net Illustrates the use of the MapOnStates macro to plot home ownership in the United States over time.

ImageTool.net Using interactors to control different aspects of the Image tool (e.g., AutoAxes and background color).

Image_wo_UI.net Demonstrates the Image2Macro, which implements much of the functionality of the Image tool with SuperviseWindow, SuperviseState, and Display. Thus this macro shows how you could build your own custom direct interactors independent of the Data Explorer user interface.

IndependentlyArrange.net Illustrates how to independently arrange a number of interactive windows within a single larger window using the SuperviseWindow and SuperviseState modules.

InsetImage.net Illustrates how to inset an independently interactive window within a larger window.

Interop.net One way of making Data Explorer modules work together. Data can be mapped onto objects at different points in the visualization to achieve desired results.

InvalidData.net How data marked as invalid are handled by various modules.

Majority.net The difference between row and column majority when using the general array format.

ManipulateGroups.net How to use ChangeGroupType and ChangeGroupMember to restructure groups.

MRI_1.net One way to visualize 2-dimensional MRI slices.

MRI_2.net One way to visualize a set of 2-dimensional MRI slices as a 3-dimensional volume.

MultipleDataSets.net Using the Inquire module and data-driven interactors to make visual programs more flexible. A relatively "generic" program that can be used with a variety of different input data sets.

PickStreamline.net Using the Pick tool to select points (on an isosurface) as the origin of streamlines in the data.

ScatterData.net Some ways to visualize scattered data

Supervise.net Demonstrates how to use SuperviseWindow, SuperviseState, and Display together in a simple visual program.

Topo.net Some ways of visualizing topographic data (in this example, two data sets sharing the same grid: elevation and a gray-scale image).

UsingAttributes.net Using attributes in a Data Explorer format file. (In this example, attributes added to the file to indicate date and source are used to caption the image.)

UsingDrape.net How to "drape" an image or other field onto a height map.

UsingEqualize.net How to use the Equalize module to emphasize features in an image.

UsingMessage.net Using the Message module to present information to the user of a visual program.

UsingMultiGrids.net Some of the differences between multigrid groups and generic groups.

UsingParse.net Using the Parse module to extract information from a string.

UsingSwitchAndRoute.net Using the Switch and Route modules to control the execution of a visual program.

Probes

Found in directory $DXROOT/samples/programs/PROBES

PlotLine2.net Using the Plot module to display 2-dimensional plots of data values.

ProbeText.net One way to place text in an image to show data values at probe points.

UsingProbes.net Using probes to control the position of a cutting plane through a 3-dimensional data set.

UsingStreakline.net Using the Streakline module to visualize a vector-field series.

Rendering

Found in directory $DXROOT/samples/programs/RENDERING

FatLines.net How to antialias lines and create multiple pixel width lines in hardware rendering.

Isolate.net Demonstrates an alternative to volume rendering using the Isolate module.

SharedCamera.net How to create two images that share the same camera. One of the images is used for rotating, zooming, and resizing; the other tracks the changes.

TextureMapOpenGL.net Using texture mapping (available only with a hardware adapter that supports OpenGL) to map an image onto a surface.

UsingClipPlane.net Using probes to control the orientation of the clipping plane.

UsingLights.net How to use lights to illuminate the object in an image.

UsingShade.net Controlling the shading properties of an object.

VolumeRenderingSimple.net, VolumeRendering.net How to create a volume rendering of a 3-dimensional data set. The first example is the simplest possible visual program; the second is more complex, with a color bar to annotate the image.

Scattered Data

Found in directory $DXROOT/samples/programs/SCATTERED

AnnotationGlyphs.net How to create your own glyphs for use with AutoGlyph and Glyph.

ConnectingScatteredPoints.net How to use the Connect and Regrid modules to create connections (interpolation elements) between points.

ScatterData.net Some ways to visualize scattered data

Sequencer

Found in directory $DXROOT/samples/programs/SEQUENCER

ContoursAndCaption.net How to draw contour lines on a plane. The position of the plane is controlled by the Sequencer, and a caption shows the current position of the plane.

FlyThrough.net, FlyThrough2.net Two ways to create a "fly through" of data.

Imide_Potential.net Visualizing a molecule in a potential field. This program also demonstrates the use of a data-driven Sequencer.

MRI_1.net One way to visualize 2-dimensional MRI slices.

MovingCamera.net Using the Sequencer to control the position of the viewing point.

MovingSheet.net Using the Sequencer to control the position of a slice through a data set.

Sort.net How to sort a field based on the y-position.

SpecialCharacters.net Displaying all of the characters in the "pitman" or "area" fonts supplied with Data Explorer. How to specify non-ASCII characters.

Streamline.net Using parameters of the Streamline module to visualize a vector field.