I have this input:
Solve[x^2 + 3 x + 2 == 0, x]
which gives this output:
{{x -> -2}, {x -> -1}}
I want the first x to be named x1
and the second x to be named x2
without having to copy the value and doing x1=-2
manually and x2=-1
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Sign up to join this communityI have this input:
Solve[x^2 + 3 x + 2 == 0, x]
which gives this output:
{{x -> -2}, {x -> -1}}
I want the first x to be named x1
and the second x to be named x2
without having to copy the value and doing x1=-2
manually and x2=-1
{x1, x2} = x /. Solve[x^2 + 3 x + 2 == 0, x]
{-2, -1}
{x1, x2} = Last @@@ Solve[x^2 + 3 x + 2 == 0, x]
(* {-2, -1} *)
or
{x1, x2} = Solve[x^2 + 3 x + 2 == 0, x][[All,1,-1]]
(* {-2, -1} *)
or
sol = Solve[x^2 + 3 x + 2 == 0, x];
sol[[All, 0]] = Last;
{x1, x2} = sol
(* {-2, -1} *)
Note: Since this question has a much simpler structure than the question linked by Artes, these tricks work for the current case (with a single-variable expression to be solved), but not for the more general case in the linked Q/A.
A certain generalization using an indexed variable:
r = FindInstance[Sin[x] == Cos[x] && -10 < x < 10, x, Reals, 15] // Values // Flatten // N
{-5.49779, 7.06858, 0.785398, -8.63938, 3.92699, -2.35619}
Map[(x[#] = r[[#]]) &, Range @ Length @ r];
{x[1], x[2], x[3], x[4], x[5]}
{-5.49779, 7.06858, 0.785398, -8.63938, 3.92699, -2.35619}