dist/joint.nowrap.js
function(ratio, opt) {

            if (!this.isDifferentiable()) return null;

            if (ratio < 0) ratio = 0;
            else if (ratio > 1) ratio = 1;

            var t = this.tAt(ratio, opt);

            return this.tangentAtT(t);
        }
function(ratio, opt) {

            if (!this.isDifferentiable()) return null;

            if (ratio < 0) ratio = 0;
            else if (ratio > 1) ratio = 1;

            var t = this.tAt(ratio, opt);

            return this.tangentAtT(t);
        }
function ( ratio , opt ) { if ( ! this . isDifferentiable ( ) ) return null ; if ( ratio < 0 ) ratio = 0 ; else if ( ratio > 1 ) ratio = 1 ; var t = this . tAt ( ratio , opt ) ; return this . tangentAtT ( t ) ; }
Returns a tangent line at requested `ratio` with precision better than requested `opt.precision`; or using `opt.subdivisions` provided.
Returns a tangent line at requested ratio with precision better than requested opt . precision ; or using opt . subdivisions provided .