The acos node returns the arc cosine of the value of its child-node.

• Minimum number of child-nodes: 1
• Maximum number of child-nodes: 1
• Valid input range: -1. to +1.
• Output range: 0 to (radians)

The acos node's value is the arc cosine, in radians, of the value of its child-node. If the input value is out of range then the acos node returns an ERROR value.

For valid value₁:

value = cos^-1(value₁)

For invalid value₁:

value = ERROR