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D.8.4.1 plot
Procedure from library surf.lib (see surf_lib).
- Usage:
plot(I); I ideal or poly
- Assume:
I defines a plane curve or a surface given by one equation
- Return:
nothing
- Note:
requires the external program ’surf’ to be installed
Example:
LIB "surf.lib"; // --------- plane curves ------------ ring rr0 = 0,(x1,x2),dp; ideal I = x1^3 - x2^2; plot(I); ring rr1 = 0,(x,y,z),dp; ideal I(1) = 2x2-1/2x3 +1-y+1; plot(I(1)); // ---- Singular Logo -------------- poly logo = ((x+3)^3 + 2*(x+3)^2 - y^2)*(x^3 - y^2)*((x-3)^3-2*(x-3)^2-y^2); plot(logo); // Steiner surface ideal J(2) = x^2*y^2+x^2*z^2+y^2*z^2-17*x*y*z; plot(J(2)); // -------------------- plot(x*(x2-y2)+z2); // E7 plot(x^3-x*y^3+z^2); // Whitney umbrella plot(z^2-x^2*y); |