code: public static boolean cs_lsolve(Scs L, float[] x) {
          int p, j, n, Lp[], Li[];
          float Lx[];
          if (!Scs_util.CS_CSC(L) || x == null)
              return (false); /* check inputs */
          n = L.n;
          Lp = L.p;
          Li = L.i;
          Lx = L.x;
          for (j = 0; j < n; j++) {
              x[j] /= Lx[Lp[j]];
              for (p = Lp[j] + 1; p < Lp[j + 1]; p++) {
                  x[Li[p]] -= Lx[p] * x[j];
              }
          }
          return true;
      }
docs: Solves a lower triangular system Lx=b where x and b are dense. x=b on
  input, solution on output.
  
  @param L
  column-compressed, lower triangular matrix
  @param x
  size n, right hand side on input, solution on output
  @return true if successful, false on error