SAGA-GIS Tool Library Documentation (v7.2.0)

Tool Field Calculator [Shapes]

The table calculator calculates a new attribute from existing attributes based on a mathematical formula. Attributes are addressed by the character 'f' (for 'field') followed by the field number (i.e.: f1, f2, ..., fn) or by the field name in square brackets (e.g.: [Field Name]).
Examples:
- sin(f1) * f2 + f3
- [Population] / [Area]

If the use no-data flag is unchecked and a no-data value appears in a record's input, no calculation is performed for it and the result is set to no-data.

Following operators are available for the formula definition:

+Addition
-Subtraction
*Multiplication
/Division
abs(x)Absolute Value
mod(x, y)Returns the floating point remainder of x/y
int(x)Returns the integer part of floating point value x
sqr(x)Square
sqrt(x)Square Root
exp(x)Exponential
pow(x, y)Returns x raised to the power of y
x ^ yReturns x raised to the power of y
ln(x)Natural Logarithm
log(x)Base 10 Logarithm
pi()Returns the value of Pi
sin(x)Sine
cos(x)Cosine
tan(x)Tangent
asin(x)Arcsine
acos(x)Arccosine
atan(x)Arctangent
atan2(x, y)Arctangent of x/y
min(x, y)Returns the minimum of values x and y
max(x, y)Returns the maximum of values x and y
gt(x, y)Returns true (1), if x is greater than y, else false (0)
x > yReturns true (1), if x is greater than y, else false (0)
lt(x, y)Returns true (1), if x is less than y, else false (0)
x < yReturns true (1), if x is less than y, else false (0)
eq(x, y)Returns true (1), if x equals y, else false (0)
x = yReturns true (1), if x equals y, else false (0)
and(x, y)Returns true (1), if both x and y are true (i.e. not 0)
or(x, y)Returns true (1), if at least one of both x and y is true (i.e. not 0)
ifelse(c, x, y)Returns x, if condition c is true (i.e. not 0), else y
rand_u(x, y)Random number, uniform distribution with minimum x and maximum y
rand_g(x, y)Random number, Gaussian distribution with mean x and standard deviation y
nodata()Returns tables's no-data value
isnodata(x)Returns true (1), if x is a no-data value, else false (0)

Parameters

 NameTypeIdentifierDescriptionConstraints
InputShapesShapes (input)TABLE--
OutputResult (*)Shapes (optional output)RESULT--
OptionsField (*)Table fieldFIELD--
Field NameTextNAME-Default: Calculation
FormulaTextFORMULA-Default: f1 + f2
SelectionBooleanSELECTION-Default: 1
Use No-DataBooleanUSE_NODATA-Default: 0
(*) optional

Command-line

Usage: saga_cmd table_calculus 2 [-TABLE <str>] [-RESULT <str>] [-FIELD <str>] [-NAME <str>] [-FORMULA <str>] [-SELECTION <str>] [-USE_NODATA <str>]
  -TABLE:<str>     	Shapes
	Shapes (input)
  -RESULT:<str>    	Result
	Shapes (optional output)
  -FIELD:<str>     	Field
	Table field
  -NAME:<str>      	Field Name
	Text
	Default: Calculation
  -FORMULA:<str>   	Formula
	Text
	Default: f1 + f2
  -SELECTION:<str> 	Selection
	Boolean
	Default: 1
  -USE_NODATA:<str>	Use No-Data
	Boolean
	Default: 0