# clump¶

clump

Contiguous groups of cells with the same value (‘clumps’)

Result = clump(expression)

expression
spatial boolean, nominal, ordinal
Result
spatial nominal

## Options¶

--diagonal or --nondiagonal

--diagonal
cells of the same value are grouped if they are within the immediate 8-cell neighbourhoodnof each other. This includes if they are to the right or left, above or below,nor are diagonal to each other (eight nearest neighbours, default).
--nondiagonal
cells of the same value are grouped only if the cells are directly to the rightnor left, or above or below each other (four nearest neighbours).

## Operation¶

Cells that have the same value on expression and are neighbours are grouped. Every group of cells satisfying these conditions is assigned a unique value on Result. Cells without neighbours with the same value on expression are also assigned a unique value on Result. The kind of connectivity needed for cells to be neighbours is specified by the option.

## Notes¶

Cells with a missing value on expression are assigned a missing value on Result.

## Group¶

This operation belongs to the group of Area operators

## Examples¶

1. • pcrcalc
binding
Result1 = Result1.map;
Expr = Expr.map;
initial
report Result1 = clump( Expr);

• python
Expr = readmap(“Expr.map”)
Result1 = clump( Expr)
 Result1.map Expr.map

2. • pcrcalc
#! –nondiagonal
binding
Result2 = Result2.map;
Expr = Expr.map;
initial
report Result2 = clump( Expr);

• python
setglobaloption(“nondiagonal”)
Expr = readmap(“Expr.map”)
Result2 = clump( Expr)
 Result2.map Expr.map

celllength

cos