| | Parametric-Equation Representative of Biconcave Erythrocytes -- from Mathematica Information Center |
 | | The representation of the shape of a biconcave erythrocyte by a set of three parametric equations was achieved by using the expressions that transform the curvilinear coordinates from the disc-cyclide coordinate system [denoted J2R; Moon and Spencer (1998), Field Theory Handbook, Springer-Verlag, Berlin] to Cartesian coordinates. |
 | | The equations are products of elliptic functions, so the challenge was to relate the three major 'shape-defining' measurements of the human erythrocyte in Cartesian coordinates to three parameters in the new curvilinear coordinates, to give a realistic representation of the shape of the membrane-surface. |
 | | The relationships between the coefficients of the Cartesian degree-4 surface that describes the discocyte and the coordinate transformation equations were derived with the aid of Mathematica; and this 'package'. |
| library.wolfram.com /infocenter/Articles/1415 (222 words) |