Solution to $x_i=a(1+sum_{ine j}frac{b_ix_j}{1+b_ix_j})$
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I'm dealing with a set of variables $x_i$ and following equations:
$forall i$ $x_i=a(1+sum_{ine j}frac{b_ix_j}{1+b_ix_j})$
Wolfram mathematica's NSolve could help, but it's not very accurate and is very limited in capacity for the number of $x_i$s, like 8.
I'm aiming for 20-100 $x_i$s so, therefore, looking for other ways like an algorithm to find $x_i$s. Any suggestion?
algorithms
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add a comment |
$begingroup$
I'm dealing with a set of variables $x_i$ and following equations:
$forall i$ $x_i=a(1+sum_{ine j}frac{b_ix_j}{1+b_ix_j})$
Wolfram mathematica's NSolve could help, but it's not very accurate and is very limited in capacity for the number of $x_i$s, like 8.
I'm aiming for 20-100 $x_i$s so, therefore, looking for other ways like an algorithm to find $x_i$s. Any suggestion?
algorithms
$endgroup$
add a comment |
$begingroup$
I'm dealing with a set of variables $x_i$ and following equations:
$forall i$ $x_i=a(1+sum_{ine j}frac{b_ix_j}{1+b_ix_j})$
Wolfram mathematica's NSolve could help, but it's not very accurate and is very limited in capacity for the number of $x_i$s, like 8.
I'm aiming for 20-100 $x_i$s so, therefore, looking for other ways like an algorithm to find $x_i$s. Any suggestion?
algorithms
$endgroup$
I'm dealing with a set of variables $x_i$ and following equations:
$forall i$ $x_i=a(1+sum_{ine j}frac{b_ix_j}{1+b_ix_j})$
Wolfram mathematica's NSolve could help, but it's not very accurate and is very limited in capacity for the number of $x_i$s, like 8.
I'm aiming for 20-100 $x_i$s so, therefore, looking for other ways like an algorithm to find $x_i$s. Any suggestion?
algorithms
algorithms
edited Dec 1 '18 at 11:09
Anais
asked Dec 1 '18 at 4:22
AnaisAnais
336
336
add a comment |
add a comment |
1 Answer
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Adding and subtracting $dfrac{x_i}{1+x_i}$ inside the parenthesis gives
$$x_i = a(1 + sum_{j}frac{x_j}{1+x_j} - frac{x_i}{1+x_i})$$
The sum does not depend on $i$; it is a constant. Can you continue?
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1
$begingroup$
Sum is not a constant and depends on all $x_i$s.
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– Anais
Dec 1 '18 at 5:34
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@Parisa It is a constant in a sense that it is the same in all equations in the system. Solve any for $x_i$, and calibrate to satisfy the constant. Another look at the problem is to assume that all $x_i$ are equal.
$endgroup$
– user58697
Dec 1 '18 at 5:39
$begingroup$
My mistake, I attempted to make the problem simpler by omitting some elements. Will change it to the original which cannot have identical $x_i$s
$endgroup$
– Anais
Dec 1 '18 at 5:47
add a comment |
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1 Answer
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1 Answer
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$begingroup$
Adding and subtracting $dfrac{x_i}{1+x_i}$ inside the parenthesis gives
$$x_i = a(1 + sum_{j}frac{x_j}{1+x_j} - frac{x_i}{1+x_i})$$
The sum does not depend on $i$; it is a constant. Can you continue?
$endgroup$
1
$begingroup$
Sum is not a constant and depends on all $x_i$s.
$endgroup$
– Anais
Dec 1 '18 at 5:34
$begingroup$
@Parisa It is a constant in a sense that it is the same in all equations in the system. Solve any for $x_i$, and calibrate to satisfy the constant. Another look at the problem is to assume that all $x_i$ are equal.
$endgroup$
– user58697
Dec 1 '18 at 5:39
$begingroup$
My mistake, I attempted to make the problem simpler by omitting some elements. Will change it to the original which cannot have identical $x_i$s
$endgroup$
– Anais
Dec 1 '18 at 5:47
add a comment |
$begingroup$
Adding and subtracting $dfrac{x_i}{1+x_i}$ inside the parenthesis gives
$$x_i = a(1 + sum_{j}frac{x_j}{1+x_j} - frac{x_i}{1+x_i})$$
The sum does not depend on $i$; it is a constant. Can you continue?
$endgroup$
1
$begingroup$
Sum is not a constant and depends on all $x_i$s.
$endgroup$
– Anais
Dec 1 '18 at 5:34
$begingroup$
@Parisa It is a constant in a sense that it is the same in all equations in the system. Solve any for $x_i$, and calibrate to satisfy the constant. Another look at the problem is to assume that all $x_i$ are equal.
$endgroup$
– user58697
Dec 1 '18 at 5:39
$begingroup$
My mistake, I attempted to make the problem simpler by omitting some elements. Will change it to the original which cannot have identical $x_i$s
$endgroup$
– Anais
Dec 1 '18 at 5:47
add a comment |
$begingroup$
Adding and subtracting $dfrac{x_i}{1+x_i}$ inside the parenthesis gives
$$x_i = a(1 + sum_{j}frac{x_j}{1+x_j} - frac{x_i}{1+x_i})$$
The sum does not depend on $i$; it is a constant. Can you continue?
$endgroup$
Adding and subtracting $dfrac{x_i}{1+x_i}$ inside the parenthesis gives
$$x_i = a(1 + sum_{j}frac{x_j}{1+x_j} - frac{x_i}{1+x_i})$$
The sum does not depend on $i$; it is a constant. Can you continue?
answered Dec 1 '18 at 5:22
user58697user58697
1,829512
1,829512
1
$begingroup$
Sum is not a constant and depends on all $x_i$s.
$endgroup$
– Anais
Dec 1 '18 at 5:34
$begingroup$
@Parisa It is a constant in a sense that it is the same in all equations in the system. Solve any for $x_i$, and calibrate to satisfy the constant. Another look at the problem is to assume that all $x_i$ are equal.
$endgroup$
– user58697
Dec 1 '18 at 5:39
$begingroup$
My mistake, I attempted to make the problem simpler by omitting some elements. Will change it to the original which cannot have identical $x_i$s
$endgroup$
– Anais
Dec 1 '18 at 5:47
add a comment |
1
$begingroup$
Sum is not a constant and depends on all $x_i$s.
$endgroup$
– Anais
Dec 1 '18 at 5:34
$begingroup$
@Parisa It is a constant in a sense that it is the same in all equations in the system. Solve any for $x_i$, and calibrate to satisfy the constant. Another look at the problem is to assume that all $x_i$ are equal.
$endgroup$
– user58697
Dec 1 '18 at 5:39
$begingroup$
My mistake, I attempted to make the problem simpler by omitting some elements. Will change it to the original which cannot have identical $x_i$s
$endgroup$
– Anais
Dec 1 '18 at 5:47
1
1
$begingroup$
Sum is not a constant and depends on all $x_i$s.
$endgroup$
– Anais
Dec 1 '18 at 5:34
$begingroup$
Sum is not a constant and depends on all $x_i$s.
$endgroup$
– Anais
Dec 1 '18 at 5:34
$begingroup$
@Parisa It is a constant in a sense that it is the same in all equations in the system. Solve any for $x_i$, and calibrate to satisfy the constant. Another look at the problem is to assume that all $x_i$ are equal.
$endgroup$
– user58697
Dec 1 '18 at 5:39
$begingroup$
@Parisa It is a constant in a sense that it is the same in all equations in the system. Solve any for $x_i$, and calibrate to satisfy the constant. Another look at the problem is to assume that all $x_i$ are equal.
$endgroup$
– user58697
Dec 1 '18 at 5:39
$begingroup$
My mistake, I attempted to make the problem simpler by omitting some elements. Will change it to the original which cannot have identical $x_i$s
$endgroup$
– Anais
Dec 1 '18 at 5:47
$begingroup$
My mistake, I attempted to make the problem simpler by omitting some elements. Will change it to the original which cannot have identical $x_i$s
$endgroup$
– Anais
Dec 1 '18 at 5:47
add a comment |
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