Band math

Create arithmetic expressions using spectral band values available on pixel and object level.

Parameters

Expression

The expression to evaluate using w[WAVE_LENGHT] or b[INDEX] to specify which bands to use.

Standard arithmetic (+,-,/,* …) and comparison operators (=,>,< …) as well as some mathematical expressions (…) and constant values can be used in expressions.

Expand to see all available operator

Arithmetic Operator	Description
`-`	Subtract
`+`	Add
`/`	Divide
`*`	Multiply
`%`	Modulo
`^`	Raised to a power

Comparison Operator	Description
`=`	Equal to
`\|` `OR`	TRUE if any of the conditions separated by OR is TRUE
`&` `AND`	TRUE if all the conditions separated by AND is TRUE
`!=` `<>`	Not equal to
`<`	Less than
`<=`	Less than or equal to
`>`	Greater than
`>=`	Greater than or equal to

Function operator	Description
`SQRT(N)`
`SIN(N)`
`COS(N)`
`EXP(N)`
`LOG(N)`
`LOG10(N)`
`AVG(N)`
`ROUND(N)`

Constants	Description
`TRUE`	Always evaluates to TRUE
`FALSE`	Always evaluates to FALSE
`INF`	token value
`PI`	approximated to 3.14159

EXAMPLE (w1700 / w2200) > w1200

Type

If the expression should be applied to Pixels or objects

Object
- Average spectrum for the object
Pixels
- Pixel values

Min

Min value for visualization

Max

Max value for visualization

Smooth

Smooth prediction result using median filter kernel

None
- No Smoothing prediction.
Low
- Smoothing using median filter kernel with 5x5 pixel box
Medium
- Smoothing using median filter kernel with 10x10 pixel box
High
- Smoothing using median filter kernel with 15x15 pixel box