Statistics Tab

The Statistics tab offers fundamental statistical operators for working with numerical data in channels.

Statistics Operators

Button	Syntax	Definition
Operate on line	selected (default) current (_cur): is appended to the selected operator all(_all): is appended to the selected operator	Your selection determines whether statistical properties are calculated on the selected lines, the current line, or all lines.The properties listed below are calculated on the line(s) selected. The Operate on line option is available only in the Channel Math tool. It is not available in Grid Math or Voxel Math.
	.min	Minimum value of the data
	.max	Maximum value of the data
	.mean	Mean (average) of values
	.range	Range of the data
	.count	Number of valid (non-dummy) data items
	.stddev	Standard deviation
	.stderr	Standard error
	.variance	Variance of data
	.countzero	Number of values equal to 0
	.countdum	Number of dummy values
	.sum	Sum of all values
	.sum2	Sum of all squared values
	.geomean	Geometric mean (only positive values)
	.minpos	Minimum positive value
	.countpos	Count of positive values
	.sum3	Sum of all cubed values
	.sum4	Sum of all 4th-power values

Application Notes

Statistical properties can be calculated on the current line, selected lines, or all lines in the database. Once calculated, these properties can be used in expressions. For example:

To subtract the mean of the current line from all selected lines, use:

C1=C0-C0_curr.mean

To instead subtract the overall mean (calculated across all lines in the database), use:

C1=C0-C0_all.mean

The Add Variable @ operator is not supported by the Statistics dot (.) functions.

Array elements (e.g. C1[1]) are supported with the Statistics dot (.) functions.