Solve is very basic at this point and can't handle complex non-linear expressions like the one you are giving it yet.
-- Andy On Sat, May 2, 2009 at 10:55 AM, antonio sacchi <[email protected]> wrote: > > Hello all, > someone can help me with this little script?? > when I try with this f(x,y): > (x+y-3)*exp(x*y) > it crash!! > I'm a newbie just started learning some script with python. > thank u !! > > import sympy > from sympy import * > > x = sympy.Symbol('x') > y = sympy.Symbol('y') > > f = input("write f(x,y) :") > print "f(x,y): ", f > > a = sympy.diff(f, x) > print "La derivata prima in x:" > sympy.pprint(a) > > b = sympy.diff(f, y) > print "La derivata prima in y:" > sympy.pprint(b) > > z = sympy.diff(a, x) > print "La derivata seconda in xx:" > sympy.pprint(z) > > k = sympy.diff(b, y) > print "La derivata seconda in yy:" > sympy.pprint(k) > > q = sympy.diff(a, y) > print "La derivata seconda in xy:" > sympy.pprint(q) > > u = sympy.diff(b, x) > print "La derivata seconda in yx:" > sympy.pprint(u) > > print "I punti critici sono:" > p = sympy.solve([a, b], [x, y]) > print p > > H = sympy.hessian(f, [x,y]) > print "La matrice Hessiana :" > print H > > D = H.det() > print "Il determinante dell'Hessiana:" > print D > > ##here when I run the script: > > scrivi la funzione :(x+y-3)*exp(x*y) > hai scritto: -(3 - x - y)*exp(x*y) > La derivata prima in x: > x*y x*y > - y*(3 - x - y)*e + e > La derivata prima in y: > x*y x*y > - x*(3 - x - y)*e + e > La derivata seconda in xx: > x*y 2 x*y > 2*y*e - y *(3 - x - y)*e > La derivata seconda in yy: > x*y 2 x*y > 2*x*e - x *(3 - x - y)*e > La derivata seconda in xy: > x*y x*y x*y x*y > x*e + y*e - (3 - x - y)*e - x*y*(3 - x - y)*e > La derivata seconda in yx: > x*y x*y x*y x*y > x*e + y*e - (3 - x - y)*e - x*y*(3 - x - y)*e > I punti critici sono: > Traceback (most recent call last): > File "E:\unico_2.py", line 36, in <module> > p = sympy.solve([a, b], [x, y]) > File "C:\Python25\Lib\site-packages\sympy\solvers\solvers.py", line > 272, in solve > raise NotImplementedError() > NotImplementedError > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sympy?hl=en -~----------~----~----~----~------~----~------~--~---
