1 | initial version |
The first trick is to use the solution_dict
parameter to get the solutions as Python dictionaries, instead of lists of expressions:
sage: sols = solve([f(0)==-2, f(2)==0, f1(4)==0, f(4)==8, f2(2)==0], a,b,c,d,e, solution_dict=True)
sage: sols
[{a: 3/16, b: -41/16, c: 87/8, d: -12, e: -2}]
As you can see, sols
is a list, with a single element, that is a dictionary:
sage: sols[0]
{a: 3/16, b: -41/16, c: 87/8, d: -12, e: -2}
sage: sols[0][a]
3/16
sage: sols[0][b]
-41/16
Now, you can use this dictionary to substitute the symbols a,b,c,d,e
with their values:
sage: f.substitute(sols[0])
x |--> 3/16*x^4 - 41/16*x^3 + 87/8*x^2 - 12*x - 2
2 | No.2 Revision |
The first trick is to use the solution_dict
parameter to get the solutions solutions
as Python dictionaries, instead of lists of expressions:
sage: relations = [f(0) == -2, f(2) == 0, f1(4) == 0, f(4) == 8, f2(2) == 0]
sage: sols = solve([f(0)==-2, f(2)==0, f1(4)==0, f(4)==8, f2(2)==0], a,b,c,d,e, solution_dict=True)
solve(relations, a, b, c, d, e, solution_dict=True)
sage: sols
sols
[{a: 3/16, b: -41/16, c: 87/8, d: -12, e: -2}]
As you can see, sols
is a list, with a single element, that is a dictionary:
sage: sols[0]
sols[0]
{a: 3/16, b: -41/16, c: 87/8, d: -12, e: -2}
sage: sols[0][a]
sols[0][a]
3/16
sage: sols[0][b]
sols[0][b]
-41/16
Now, you can use this dictionary to substitute substitute
the symbols
, a,b,c,d,eab
, c
, d
, e
with their values:
sage: f.substitute(sols[0])
f.substitute(sols[0])
x |--> 3/16*x^4 - 41/16*x^3 + 87/8*x^2 - 12*x - 2