function fromRotation$4(out, rad) {
    var s = Math.sin(rad);
    var c = Math.cos(rad);
    out[0] = c;
    out[1] = s;
    out[2] = -s;
    out[3] = c;
    return out;
  }
Creates a matrix from a given angle
This is equivalent to (but much faster than):

    mat2.identity(dest);
    mat2.rotate(dest, dest, rad);

@param {mat2} out mat2 receiving operation result
@param {Number} rad the angle to rotate the matrix by
@returns {mat2} out