iDevOS CALC "ACOS" Command

Get the arc (inverse) cosine.

Description

CALC( y, a, "ACOS" );      // y = acos(a)     = arc cosine of a
CALC( y, a, b, "ACOS" );   // y = acos(a / b) = arc cosine of a divided b

This command returns the angle y as the arc cosine (or inverse cosine) of a. If the divider value b is specified then a is divided by b before the trigonometric calculation is performed.

The angle y by default is specified in Degrees. Angles used in trigonometric functions can be set globally to use Radians by the SYSTEM.angles property.

Note: The value passed into the trigonometric function (a or a/b) must be within -1 to +1 (inclusive) otherwise a system error will be generated. It is the responsibility of the user to check this.

Trigonometric functions: "COS", "SIN", "TAN", "ACOS", "ASIN", "ATAN", "ATAN2", "COSH", "SINH", "TANH", "ACOSH", "ASINH", "ATANH".

Parameters

y

Calculation result.
Parameter type: entity name of a numeric variable (eg U8, S32, FLT3 etc).

a and b

Input values.
Parameter type: immediate number, or entity name of a numeric variable (eg U8, S32, FLT3 etc).

"ACOS"

CALC command operator.
Parameter type: immediate string.

Examples

Example 1

VAR(df,  0.0,    FLT4); // result
VAR(af1, 0.7071, FLT4); // value
VAR(af2, 3.5355, FLT4); // value
VAR(bf,  5,      FLT4); // divider

CALC(df, af1, "ACOS");     // df = 45.0005

CALC(df, af2, bf, "ACOS" ); // df = 45.0005