Preferences

Projection Preferences: Preferences relating to the currently selected projection method.

Projector Preferences: Coordinate

First and second dimension: control which dimensions of the high-dimensional data are projected to the horizontal and vertical axes of the display.

Automatically use most variant dimensions: If this is selected then the program selects the two most variant axes of the high dimensional dataset for coordinate projection.

Projector Preferences: Sammon

Step size How much the points should be incremented at each iteration of the Sammon map. The bigger the step size is the faster the projection algorithm will run but if the step size is too large the projected image will explode. One can generally experiment with different step sizes to get the right one. If iteration is progressing very slowly, one can just try something large, like 100, 300, or even 1000. If the dataset "explodes" (in which case everything in the display may contract to a point), press the randomize button to start over. Tip: A step size of a little less than 1 is good for objects with about a dozen points while a step size in the hundreds is good for objects with hundreds of points.

Projector Preferences: PCA

There are no specific preferences for PCA.

General Preferences

Tolerance: When datasets are initially loaded, or when data are added to an existing dataset we want to ignore repeated points. Even if a new point is not exactly the same as some other point in the set, it may be "close enough" to be considered the same point. This field allows one to set a tolerance level for deciding whether two points are the same. If "2" is specified in this field, for example, then any new point within a radius of 2 of some existing point will not be added to the dataset. Note: Repeated points are allowed in the low-dimensional dataset; this field only applies to the high-dimensional data.

Graphics / GUI Preferences: Preferences relating to the appearances of the dots. See datapoint coloring for details.

General Preferences: General preferences relating to projected data.

Adding New Data Point: Allows user to choose how new points will be added to the dataset. These methods are described here.