A function in the expr command that computes the sine of an angle. The angle is expressed in radians.
Not to be confused with the theological concept [L1 ].
The sine could be approximated by :
proc sine x { return [expr {1.2732396*$x - 0.4052847*$x*abs($x)}] }
proc sinus x { if {$x < 0} then { set sine [expr {$x*(1.27323954 + .405284735 * $x)}] } else { set sine [expr {$x*(1.27323954 - 0.405284735 * $x)}] } if {$sine < 0} then { set sine [expr {$sine*(-0.225 * ($sine + 1) + 1)}] } else { set sine [expr {$sine*(0.225 * ($sine - 1) + 1)}] } return $sine }