Bitmap operators

Several context-sensitive pages in the Variable Properties dialog box are displayed for virtual variables. The pages that are displayed depend on the operator that was used to create the virtual variables.

One or more of the following virtual variable pages will be present when Bitmap operators are used:

Data Range Bitmap page
Line Bitmap page

Mask page

Region Bitmap page

Roll Range page

Target Samples Bitmap page

Data Range Bitmap page

The Data range bitmap page is displayed on the Variable Properties dialog box if the Data range bitmap operator has been applied to create the selected virtual variable.

Settings

Description

Minimum in-range value

Specify the minimum and maximum values of the data range for the bitmap.

When the operand is a color variable, settings can be entered for the Red, Green and Blue components individually.

When the operand is an angular position variable, settings can be entered for the Minor-axis and the Major-axis.

Data values in the operand variable that are in range are given a value of 'true'.

Data values in the operand variable that are below the minimum and above the maximum will be given a bitmap value of 'false'.

Maximum in-range value

Note: No data values in the operand variable will be translated to 'false' for the bitmap.

Line Bitmap page

The Line Bitmap page is displayed on the Variable Properties dialog box if the Line Bitmap operator has been applied to create the selected virtual variable.

Settings

Description

Start line

Specify the two lines to use to create the bitmap. Datapoints located above the start line or below the stop line are assigned a value of 'false'.

Note: The start line must be located at a depth that is above depth of the stop line or all data will be marked as 'false'.

Stop line

Invert output

Select this option to invert the output, i.e. mark 'false' datapoints as 'true' and vice versa.

Mask page

The Mask page is displayed on the Variable Properties dialog box if the Mask operator has been applied to create the selected virtual variable.

Setting

Description

Set masked values to

Select the value that should be assigned to samples where the bitmap is false.

Region Bitmap page

This page is displayed if the Region Bitmap operator has been applied to create the selected virtual variable.

Settings

Description

Region type

Choose one or all region type for the bitmap

Region class

Choose one or all region classes for the bitmap

Invert output

Select this check box to invert the output, i.e. mark data points outside matching regions as 'true' and data points within matching regions as 'false'.

Roll Range Bitmap page

The Roll Range page is displayed on the Variable Properties dialog box if the Roll Range Bitmap operator has been applied to create the selected virtual variable. This operator creates a bitmap using the ping geometry of operand 1. Every data point in each output ping will be true if the roll (from operand 2) at the time of that ping was within the limits specified here, and false otherwise.

Settings

Description

Minimum in-range roll (degrees)

Specify the minimum and maximum values of the roll for the bitmap.

Data values in the operand variable for which the roll is in the specified range (inclusive) are given a value of 'true', otherwise 'false'.

Maximum in-range roll (degrees)

Target Samples Bitmap page

The Target Samples Bitmap page is displayed on the Variable properties dialog box if the Target Samples bitmap operator had been applied to create the selected virtual variable.

Setting

Description

Near margin

The Near margin (m) is subtracted from the range of each single target (in operand 2), to determine the start of the acceptable range (for each single target).

Far margin The Far margin (m) and the single target's display thickness are added to the range of each single target (in operand 2) to determine the end of the acceptable range (for each single target).

See also

Variable Properties dialog box
About virtual variables
Operators