1 d3.transform = function(string) {

     2   d3_transformG.setAttribute("transform", string);

     3   return new d3_transform(d3_transformG.transform.baseVal.consolidate().matrix);

     4 };

     5 

     6 // Compute x-scale and normalize the first row.

     7 // Compute shear and make second row orthogonal to first.

     8 // Compute y-scale and normalize the second row.

     9 // Finally, compute the rotation.

    10 function d3_transform(m) {

    11   var r0 = [m.a, m.b],

    12       r1 = [m.c, m.d],

    13       kx = d3_transformNormalize(r0),

    14       kz = d3_transformDot(r0, r1),

    15       ky = d3_transformNormalize(d3_transformCombine(r1, r0, -kz));

    16   this.translate = [m.e, m.f];

    17   this.rotate = Math.atan2(m.b, m.a) * d3_transformDegrees;

    18   this.scale = [kx, ky || 0];

    19   this.skew = ky ? kz / ky * d3_transformDegrees : 0;

    20 };

    21 

    22 d3_transform.prototype.toString = function() {

    23   return "translate(" + this.translate

    24       + ")rotate(" + this.rotate

    25       + ")skewX(" + this.skew

    26       + ")scale(" + this.scale

    27       + ")";

    28 };

    29 

    30 function d3_transformDot(a, b) {

    31   return a[0] * b[0] + a[1] * b[1];

    32 }

    33 

    34 function d3_transformNormalize(a) {

    35   var k = Math.sqrt(d3_transformDot(a, a));

    36   a[0] /= k;

    37   a[1] /= k;

    38   return k;

    39 }

    40 

    41 function d3_transformCombine(a, b, k) {

    42   a[0] += k * b[0];

    43   a[1] += k * b[1];

    44   return a;

    45 }

    46 

    47 var d3_transformG = document.createElementNS(d3.ns.prefix.svg, "g"),

    48     d3_transformDegrees = 180 / Math.PI;