Name
Atn Function
Syntax
Atn(number
)
-
number
Use: Required
Data Subtype: Numeric
Any numeric expression, representing the ratio of two sides of a right angle triangle.
Return Value
The return value is a Double data subtype representing the arctangent
of number
in the range -pi/2 to pi/2
radians.
Description
Takes the ratio of two sides of a right triangle
(number
) and returns the corresponding
angle in radians. The ratio is the length of the side opposite the
angle divided by the length of the side adjacent to the angle.
Rules at a Glance
If no number is specified, a runtime error is generated.
The return value of
Atn
is in radians, not degrees.
Example
<% Dim dblSideAdj Dim dblSideOpp Dim dblRatio Dim dblAtangent dblSideAdj = 50.25 dblSideOpp = 75.5 dblRatio = dblSideOpp / dblSideAdj dblAtangent = Atn(dblRatio) 'convert from radians to degrees dblDegrees = dblAtangent * (180 / 3.142) Response.Write dblDegrees & " Degrees" %>
Programming Tips & Gotchas
To convert degrees to radians, multiply degrees by pi/180.
To convert radians to degrees, multiply radians by 180/pi.
Don’t confuse
Atn
with the cotangent.Atn
is the inverse trigonometric function ofTan
, as opposed to the simple inverse ofTan
.
See Also
Tan Function |
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