ACOS
Returns the arc cosine of an expression that represents a numerical value. The evaluated expression must return a value whose absolute value 
. The value returned by ACOS lies in the range [0,
], that is, 0 < ACOS(x) < 
.
. The value returned by ACOS lies in the range [0, ], that is, 0 < ACOS(x) < . Format
ACOS (x)
Argument
X | Any valid expression that evaluates to a real number. |
Example
The following function calculates the angle (in radians) between the line from marker_11 to marker_21 and the line from marker_41 to marker_31:
ACOS((DX(marker_21, marker_11) * DX(marker_31, marker_41) +
DY(marker_21, marker_11) * DY(marker_31, marker_41) +
DZ(marker_21, marker_11) * DZ(marker_31, marker_41))/
(DM(marker_21, marker_11) * DM(marker_31, marker_41))
DY(marker_21, marker_11) * DY(marker_31, marker_41) +
DZ(marker_21, marker_11) * DZ(marker_31, marker_41))/
(DM(marker_21, marker_11) * DM(marker_31, marker_41))