===== Primitive: Torus with X-axis =====

**Definition**: <m>{r_0}^2-(x-x_0)^2-(y-y_0)^2-(z-z_0)^2-R^2+2*R*sqrt{(z-z_0)^2+(y-y_0)^2}</m>

**Call**: hfTorusX(x,center,R,r0);

**Parameters**:

x - point coordinates array

center - center array

R - radius of revolution

r0 - disk radius

**Test file**: [[http://hyperfun.org/torus.hf|torus.hf]]

===== Primitive: Torus with Y-axis =====

**Definition**: <m>{r_0}^2-(x-x_0)^2-(y-y_0)^2-(z-z_0)^2-R^2+2*R*sqrt{(z-z_0)^2+(x-x_0)^2}</m>

**Call**: hfTorusY(x,center,R,r0);

**Parameters**:

x - point coordinates array

center - center array

R - radius of revolution

r0 - disk radius

**Test file**: [[http://hyperfun.org/torus.hf|torus.hf]]

===== Primitive: Torus with Z-axis =====

**Definition**: <m>{r_0}^2-(x-x_0)^2-(y-y_0)^2-(z-z_0)^2-R^2+2*R*sqrt{(x-x_0)^2+(y-y_0)^2}</m>

**Call**: hfTorusZ(x,center,R,r0);

**Parameters**:

x - point coordinates array

center - center array

R - radius of revolution

r0 - disk radius

**Test file**: [[http://hyperfun.org/torus.hf|torus.hf]]