subtract

Boolean subtraction of one 3-D geometry from another

Since R2025a

Syntax

g3 = subtract(g1,g2)

Description

g3 = subtract(g1,g2) subtracts a 3-D geometry g2 from a 3-D geometry g1.

Examples

Create Sphere with Cutout Piece

Cut out a quarter of a sphere by subtracting a cube from it.

Create and plot a geometry of a sphere.

gsphere = multisphere(5);
pdegplot(gsphere)

Create and plot a geometry of a cuboid.

gcube = multicuboid(5,5,10);
gcube = translate(gcube,[2.5 -2.5 -5]);
figure
pdegplot(gcube)

Convert both geometries to fegeometry objects.

gsphere = fegeometry(gsphere);
gcube = fegeometry(gcube);

Subtract the cuboid from the sphere using the Boolean subtraction operation.

g = subtract(gsphere,gcube);

Plot the resulting geometry.

figure
pdegplot(g,CellLabels="on",FaceAlpha=0.3)

Subtract Cube from Sphere

Subtract a cube from a larger sphere by using the Boolean subtraction operation.

Create and plot a geometry of a sphere.

gsphere = multisphere(5);
pdegplot(gsphere)

Create and plot a geometry of a cube.

gcube = multicuboid(6,6,6,Zoffset=-3);
figure
pdegplot(gcube)

Convert both geometries to fegeometry objects.

gsphere = fegeometry(gsphere);
gcube = fegeometry(gcube);

Subtract the cube from the sphere using the Boolean subtraction operation.

g = subtract(gsphere,gcube);

Plot the resulting geometry.

figure
pdegplot(g,CellLabels="on",FaceAlpha=0.3)

Input Arguments

g1 — 3-D geometry

fegeometry object

3-D geometry, specified as an fegeometry object.

g2 — 3-D geometry

fegeometry object

3-D geometry, specified as an fegeometry object.

Output Arguments

g3 — Combined geometry

fegeometry object

Combined geometry, returned as an fegeometry object.

Limitations

• subtract works only on 3-D geometries. Use decsg to subtract 2-D geometries.

Version History

Introduced in R2025a