acos()

    
Also See:   abs asin atan atan2 ceil cos cosh exp floor fmod int log log10 power random rnd sin sinh sqrt srandom tan tanh

Report a language bug  |  Report a documentation error
Returns the arccosine of number. The results are returned in radians.
Syntax 
acos( number )
Returns the results in radians.
+ Add a note
User Annotations: acos
Ray Yates : mivascript at, pcinet d0t com
02/09/2012 12:07 a.m. 
A bug in acos(x) causes it to return cos(x). This is true through version 5.14. The derivitive function below was provided by Jon Burchmore and returns the correct value.
<MvFUNCTION NAME = "arccos" PARAMETERS = "val" STANDARDOUTPUTLEVEL = "">
   <MvASSIGN NAME = "l.negval" VALUE = "{ 0 - l.val }">
   <MvFUNCTIONRETURN VALUE = "{ atan( l.negval / sqrt( l.negval * l.val + 1 ) ) + 2 * atan( 1 ) }">
</MvFUNCTION>