code: function(rhs) {
  
              console.warn('deprecated');
  
              var n = rhs.length;
              // `x` is a solution vector.
              var x = [];
              var tmp = [];
              var b = 2.0;
  
              x[0] = rhs[0] / b;
  
              // Decomposition and forward substitution.
              for (var i = 1; i < n; i++) {
                  tmp[i] = 1 / b;
                  b = (i < n - 1 ? 4.0 : 3.5) - tmp[i];
                  x[i] = (rhs[i] - x[i - 1]) / b;
              }
  
              for (i = 1; i < n; i++) {
                  // Backsubstitution.
                  x[n - i - 1] -= tmp[n - i] * x[n - i];
              }
  
              return x;
          }
docs: Solves a tridiagonal system for one of coordinates (x or y) of first Bezier control points. @deprecated @param rhs Right hand side vector. @return Solution vector.