Possible bug in Solve function?
In 11.3.0 for Microsoft Windows (64-bit) (March 7, 2018)
writing:
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0,
D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0,
D[f[w, x, y, z], z] == 0};
sol = Solve[eqn];
Table[eqn /. sol[[n]], {n, Length[sol]}]
I get:
{{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True}}
from which there are four wrong solutions.
Am I wrong or is it a Solve
bug?
equation-solving bugs
add a comment |
In 11.3.0 for Microsoft Windows (64-bit) (March 7, 2018)
writing:
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0,
D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0,
D[f[w, x, y, z], z] == 0};
sol = Solve[eqn];
Table[eqn /. sol[[n]], {n, Length[sol]}]
I get:
{{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True}}
from which there are four wrong solutions.
Am I wrong or is it a Solve
bug?
equation-solving bugs
You could useList@ToRules@Reduce[eqn, {x, y, z, w}]
to get all valid solutions. Filter for those that only have numeric values on the RHS of->
.
– Szabolcs
yesterday
Select[sol, And @@ eqn /. # &]
– Bob Hanlon
yesterday
2
Next time, please do not add the bugs tag yourself on a question. The tag is only supposed to be added after your observations have been confirmed by other users.
– J. M. is computer-less♦
yesterday
add a comment |
In 11.3.0 for Microsoft Windows (64-bit) (March 7, 2018)
writing:
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0,
D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0,
D[f[w, x, y, z], z] == 0};
sol = Solve[eqn];
Table[eqn /. sol[[n]], {n, Length[sol]}]
I get:
{{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True}}
from which there are four wrong solutions.
Am I wrong or is it a Solve
bug?
equation-solving bugs
In 11.3.0 for Microsoft Windows (64-bit) (March 7, 2018)
writing:
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0,
D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0,
D[f[w, x, y, z], z] == 0};
sol = Solve[eqn];
Table[eqn /. sol[[n]], {n, Length[sol]}]
I get:
{{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True},
{False, True, True, False},
{True, True, True, True},
{True, True, True, True}}
from which there are four wrong solutions.
Am I wrong or is it a Solve
bug?
equation-solving bugs
equation-solving bugs
asked yesterday
TeM
1,970621
1,970621
You could useList@ToRules@Reduce[eqn, {x, y, z, w}]
to get all valid solutions. Filter for those that only have numeric values on the RHS of->
.
– Szabolcs
yesterday
Select[sol, And @@ eqn /. # &]
– Bob Hanlon
yesterday
2
Next time, please do not add the bugs tag yourself on a question. The tag is only supposed to be added after your observations have been confirmed by other users.
– J. M. is computer-less♦
yesterday
add a comment |
You could useList@ToRules@Reduce[eqn, {x, y, z, w}]
to get all valid solutions. Filter for those that only have numeric values on the RHS of->
.
– Szabolcs
yesterday
Select[sol, And @@ eqn /. # &]
– Bob Hanlon
yesterday
2
Next time, please do not add the bugs tag yourself on a question. The tag is only supposed to be added after your observations have been confirmed by other users.
– J. M. is computer-less♦
yesterday
You could use
List@ToRules@Reduce[eqn, {x, y, z, w}]
to get all valid solutions. Filter for those that only have numeric values on the RHS of ->
.– Szabolcs
yesterday
You could use
List@ToRules@Reduce[eqn, {x, y, z, w}]
to get all valid solutions. Filter for those that only have numeric values on the RHS of ->
.– Szabolcs
yesterday
Select[sol, And @@ eqn /. # &]
– Bob Hanlon
yesterday
Select[sol, And @@ eqn /. # &]
– Bob Hanlon
yesterday
2
2
Next time, please do not add the bugs tag yourself on a question. The tag is only supposed to be added after your observations have been confirmed by other users.
– J. M. is computer-less♦
yesterday
Next time, please do not add the bugs tag yourself on a question. The tag is only supposed to be added after your observations have been confirmed by other users.
– J. M. is computer-less♦
yesterday
add a comment |
2 Answers
2
active
oldest
votes
Thanks for asking! In version 9.0 only 16 solutions are returned and they are all valid. In version 10.2 there are 20 solutions, with the extra 4 all being invalid. Contragulations! I think you found a bug. You may want to click "Help", then "Give Feedback...", and then fill out the form in your browser to report.
As another answer notes, you can always try Reduce
instead which may give better results in some cases, but Solve
is usually what you want.
Well, it will mean that the next version will be the first calculation I will perform. Thank you! ^_^
– TeM
yesterday
1
@TeM You should report it to Wolfram first, otherwise there's no chance for it to get fixed.
– Szabolcs
yesterday
@Szabolcs: Could you direct me where I can do it correctly?
– TeM
yesterday
3
@TeM wolfram.com/support/contact
– Szabolcs
yesterday
add a comment |
You can use Reduce
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0, D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0, D[f[w, x, y, z], z] == 0};
red = Reduce[eqn, Backsubstitution -> True]
$left(z=0land x=0land w=-sqrt{1-y^2}right)lor left(z=0land x=0land w=sqrt{1-y^2}right)lor left(z=0land y=0land
w=-sqrt{1-x^2}right)lor left(z=0land y=0land w=sqrt{1-x^2}right)lor (z=0land y=-1land x=0land w=0)lor (z=0land y=0land x=0land
w=-1)lor (z=0land y=0land x=0land w=1)lor (z=0land y=1land x=0land w=0)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land
x=-frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)\
lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)$
First@eqn //. {ToRules[red]}
{True, True, True, True, True, True, True, True, True, True, True,
True, True, True, True, True}
Yes, of course, I had already tried. I was almost certain it was a bug fromSolve
, so I pointed out. Thank you very much anyway, always very kind!
– TeM
yesterday
3
I believeSolve
use the functionReduce
under the hood. when you removeBacksubstitution -> True
, you'll find implicit solution, somehowSolve
messes up somewhere and it is definitely a bug..
– Okkes Dulgerci
yesterday
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
Thanks for asking! In version 9.0 only 16 solutions are returned and they are all valid. In version 10.2 there are 20 solutions, with the extra 4 all being invalid. Contragulations! I think you found a bug. You may want to click "Help", then "Give Feedback...", and then fill out the form in your browser to report.
As another answer notes, you can always try Reduce
instead which may give better results in some cases, but Solve
is usually what you want.
Well, it will mean that the next version will be the first calculation I will perform. Thank you! ^_^
– TeM
yesterday
1
@TeM You should report it to Wolfram first, otherwise there's no chance for it to get fixed.
– Szabolcs
yesterday
@Szabolcs: Could you direct me where I can do it correctly?
– TeM
yesterday
3
@TeM wolfram.com/support/contact
– Szabolcs
yesterday
add a comment |
Thanks for asking! In version 9.0 only 16 solutions are returned and they are all valid. In version 10.2 there are 20 solutions, with the extra 4 all being invalid. Contragulations! I think you found a bug. You may want to click "Help", then "Give Feedback...", and then fill out the form in your browser to report.
As another answer notes, you can always try Reduce
instead which may give better results in some cases, but Solve
is usually what you want.
Well, it will mean that the next version will be the first calculation I will perform. Thank you! ^_^
– TeM
yesterday
1
@TeM You should report it to Wolfram first, otherwise there's no chance for it to get fixed.
– Szabolcs
yesterday
@Szabolcs: Could you direct me where I can do it correctly?
– TeM
yesterday
3
@TeM wolfram.com/support/contact
– Szabolcs
yesterday
add a comment |
Thanks for asking! In version 9.0 only 16 solutions are returned and they are all valid. In version 10.2 there are 20 solutions, with the extra 4 all being invalid. Contragulations! I think you found a bug. You may want to click "Help", then "Give Feedback...", and then fill out the form in your browser to report.
As another answer notes, you can always try Reduce
instead which may give better results in some cases, but Solve
is usually what you want.
Thanks for asking! In version 9.0 only 16 solutions are returned and they are all valid. In version 10.2 there are 20 solutions, with the extra 4 all being invalid. Contragulations! I think you found a bug. You may want to click "Help", then "Give Feedback...", and then fill out the form in your browser to report.
As another answer notes, you can always try Reduce
instead which may give better results in some cases, but Solve
is usually what you want.
edited yesterday
answered yesterday
Somos
3628
3628
Well, it will mean that the next version will be the first calculation I will perform. Thank you! ^_^
– TeM
yesterday
1
@TeM You should report it to Wolfram first, otherwise there's no chance for it to get fixed.
– Szabolcs
yesterday
@Szabolcs: Could you direct me where I can do it correctly?
– TeM
yesterday
3
@TeM wolfram.com/support/contact
– Szabolcs
yesterday
add a comment |
Well, it will mean that the next version will be the first calculation I will perform. Thank you! ^_^
– TeM
yesterday
1
@TeM You should report it to Wolfram first, otherwise there's no chance for it to get fixed.
– Szabolcs
yesterday
@Szabolcs: Could you direct me where I can do it correctly?
– TeM
yesterday
3
@TeM wolfram.com/support/contact
– Szabolcs
yesterday
Well, it will mean that the next version will be the first calculation I will perform. Thank you! ^_^
– TeM
yesterday
Well, it will mean that the next version will be the first calculation I will perform. Thank you! ^_^
– TeM
yesterday
1
1
@TeM You should report it to Wolfram first, otherwise there's no chance for it to get fixed.
– Szabolcs
yesterday
@TeM You should report it to Wolfram first, otherwise there's no chance for it to get fixed.
– Szabolcs
yesterday
@Szabolcs: Could you direct me where I can do it correctly?
– TeM
yesterday
@Szabolcs: Could you direct me where I can do it correctly?
– TeM
yesterday
3
3
@TeM wolfram.com/support/contact
– Szabolcs
yesterday
@TeM wolfram.com/support/contact
– Szabolcs
yesterday
add a comment |
You can use Reduce
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0, D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0, D[f[w, x, y, z], z] == 0};
red = Reduce[eqn, Backsubstitution -> True]
$left(z=0land x=0land w=-sqrt{1-y^2}right)lor left(z=0land x=0land w=sqrt{1-y^2}right)lor left(z=0land y=0land
w=-sqrt{1-x^2}right)lor left(z=0land y=0land w=sqrt{1-x^2}right)lor (z=0land y=-1land x=0land w=0)lor (z=0land y=0land x=0land
w=-1)lor (z=0land y=0land x=0land w=1)lor (z=0land y=1land x=0land w=0)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land
x=-frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)\
lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)$
First@eqn //. {ToRules[red]}
{True, True, True, True, True, True, True, True, True, True, True,
True, True, True, True, True}
Yes, of course, I had already tried. I was almost certain it was a bug fromSolve
, so I pointed out. Thank you very much anyway, always very kind!
– TeM
yesterday
3
I believeSolve
use the functionReduce
under the hood. when you removeBacksubstitution -> True
, you'll find implicit solution, somehowSolve
messes up somewhere and it is definitely a bug..
– Okkes Dulgerci
yesterday
add a comment |
You can use Reduce
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0, D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0, D[f[w, x, y, z], z] == 0};
red = Reduce[eqn, Backsubstitution -> True]
$left(z=0land x=0land w=-sqrt{1-y^2}right)lor left(z=0land x=0land w=sqrt{1-y^2}right)lor left(z=0land y=0land
w=-sqrt{1-x^2}right)lor left(z=0land y=0land w=sqrt{1-x^2}right)lor (z=0land y=-1land x=0land w=0)lor (z=0land y=0land x=0land
w=-1)lor (z=0land y=0land x=0land w=1)lor (z=0land y=1land x=0land w=0)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land
x=-frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)\
lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)$
First@eqn //. {ToRules[red]}
{True, True, True, True, True, True, True, True, True, True, True,
True, True, True, True, True}
Yes, of course, I had already tried. I was almost certain it was a bug fromSolve
, so I pointed out. Thank you very much anyway, always very kind!
– TeM
yesterday
3
I believeSolve
use the functionReduce
under the hood. when you removeBacksubstitution -> True
, you'll find implicit solution, somehowSolve
messes up somewhere and it is definitely a bug..
– Okkes Dulgerci
yesterday
add a comment |
You can use Reduce
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0, D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0, D[f[w, x, y, z], z] == 0};
red = Reduce[eqn, Backsubstitution -> True]
$left(z=0land x=0land w=-sqrt{1-y^2}right)lor left(z=0land x=0land w=sqrt{1-y^2}right)lor left(z=0land y=0land
w=-sqrt{1-x^2}right)lor left(z=0land y=0land w=sqrt{1-x^2}right)lor (z=0land y=-1land x=0land w=0)lor (z=0land y=0land x=0land
w=-1)lor (z=0land y=0land x=0land w=1)lor (z=0land y=1land x=0land w=0)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land
x=-frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)\
lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)$
First@eqn //. {ToRules[red]}
{True, True, True, True, True, True, True, True, True, True, True,
True, True, True, True, True}
You can use Reduce
f[w_, x_, y_, z_] := w*x^2*y^3 - z*(w^2 + x^2 + y^2 - 1)
eqn = {D[f[w, x, y, z], w] == 0, D[f[w, x, y, z], x] == 0,
D[f[w, x, y, z], y] == 0, D[f[w, x, y, z], z] == 0};
red = Reduce[eqn, Backsubstitution -> True]
$left(z=0land x=0land w=-sqrt{1-y^2}right)lor left(z=0land x=0land w=sqrt{1-y^2}right)lor left(z=0land y=0land
w=-sqrt{1-x^2}right)lor left(z=0land y=0land w=sqrt{1-x^2}right)lor (z=0land y=-1land x=0land w=0)lor (z=0land y=0land x=0land
w=-1)lor (z=0land y=0land x=0land w=1)lor (z=0land y=1land x=0land w=0)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land
x=-frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=-frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=-frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land
w=-frac{1}{sqrt{6}}right)lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=-frac{1}{sqrt{3}}land
w=frac{1}{sqrt{6}}right)\
lor left(z=frac{1}{4 sqrt{3}}land y=frac{1}{sqrt{2}}land x=frac{1}{sqrt{3}}land w=frac{1}{sqrt{6}}right)$
First@eqn //. {ToRules[red]}
{True, True, True, True, True, True, True, True, True, True, True,
True, True, True, True, True}
answered yesterday
Okkes Dulgerci
4,1851816
4,1851816
Yes, of course, I had already tried. I was almost certain it was a bug fromSolve
, so I pointed out. Thank you very much anyway, always very kind!
– TeM
yesterday
3
I believeSolve
use the functionReduce
under the hood. when you removeBacksubstitution -> True
, you'll find implicit solution, somehowSolve
messes up somewhere and it is definitely a bug..
– Okkes Dulgerci
yesterday
add a comment |
Yes, of course, I had already tried. I was almost certain it was a bug fromSolve
, so I pointed out. Thank you very much anyway, always very kind!
– TeM
yesterday
3
I believeSolve
use the functionReduce
under the hood. when you removeBacksubstitution -> True
, you'll find implicit solution, somehowSolve
messes up somewhere and it is definitely a bug..
– Okkes Dulgerci
yesterday
Yes, of course, I had already tried. I was almost certain it was a bug from
Solve
, so I pointed out. Thank you very much anyway, always very kind!– TeM
yesterday
Yes, of course, I had already tried. I was almost certain it was a bug from
Solve
, so I pointed out. Thank you very much anyway, always very kind!– TeM
yesterday
3
3
I believe
Solve
use the function Reduce
under the hood. when you remove Backsubstitution -> True
, you'll find implicit solution, somehow Solve
messes up somewhere and it is definitely a bug..– Okkes Dulgerci
yesterday
I believe
Solve
use the function Reduce
under the hood. when you remove Backsubstitution -> True
, you'll find implicit solution, somehow Solve
messes up somewhere and it is definitely a bug..– Okkes Dulgerci
yesterday
add a comment |
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You could use
List@ToRules@Reduce[eqn, {x, y, z, w}]
to get all valid solutions. Filter for those that only have numeric values on the RHS of->
.– Szabolcs
yesterday
Select[sol, And @@ eqn /. # &]
– Bob Hanlon
yesterday
2
Next time, please do not add the bugs tag yourself on a question. The tag is only supposed to be added after your observations have been confirmed by other users.
– J. M. is computer-less♦
yesterday