code: public void designPipe( double[][] diameters, double tau, double g, double maxd, double c, StringBuilder strWarnings ) {
  
          switch( this.pipeSectionType ) {
          case 1:
              designCircularPipe(diameters, tau, g, maxd, strWarnings);
              break;
          case 2:
              designRectangularPipe(tau, g, maxd, c, strWarnings);
              break;
          case 3:
              designTrapeziumPipe(tau, g, maxd, c, strWarnings);
              break;
          default:
              designCircularPipe(diameters, tau, g, maxd, strWarnings);
              break;
          }
      }
docs: Calculate the dimension of the pipes.
  
  <p>
  It switch between several section geometry.
  </p>
  
  
  @param diameters
  matrix with the commercial diameters.
  @param tau
  tangential stress at the bottom of the pipe..
  @param g
  fill degree.
  @param maxd
  maximum diameter.
  @param c
  is a geometric expression b/h where h is the height and b base
  (only for rectangular or trapezium shape).