Re: [R] solving simultaneous Equations in R
On 11-12-2013, at 23:56, eliza botto eliza_bo...@hotmail.com wrote:
Dear Berend,
Thankyou very much indeed for you reply. By taking help from your previous
reply @ http://r.789695.n4.nabble.com/Simultaneous-equations-td2524645.html i
was able to generate the following loop for the calculation of x=x[1] and
y=x[2].
fun - function(x) {
f - numeric(length(x))
# read as:
f[1] -
1-0.514-(gamma(1/x[1])*gamma(2/x[1]-1/x[2]))/(gamma(2/x[1])*gamma(1/x[1]-1/x[2]))
f[2] - 0.57-
(gamma(1/x[1]-1/x[2])/gamma(1/x[1])-3*gamma(2/x[1]-1/x[2])/gamma(2/x[1])+2*gamma(3/x[1]-1/x[2])/gamma(3/x[1]))/(gamma(1/x[1]-1/x[2])/gamma(1
/x[1])-gamma(2/x[1]-1/x[2])/gamma(2/x[1]))
f
}
startx - c(0.1,0.15) # start the answer search here
answers-as.data.frame(nleqslv(startx,fun))
answers
What i cant understand is the concept involved for setting startx. my x[1]
should always be smaller than x[2] and they both should be less than 1. how
can i demonstrate it to startx command line?
I don’t quite understand what you you mean.
Your starting values obey the restrictions you specify (if that is what you
meant).
The solution vector has all elements 1. But it is a solution.
Do you mean that you want a solution satisfying the constraints you mention?
I cannot tell if that is possible.
Generally speaking a square system of equations is solved or not.
Sometimes you can vary the starting values to get a different solution that
obeys the specified constraints.
If these constraints are necessary you are not solving a system of equations
but trying to find a parameter set that satisfies certain criteria. Together
with a criterion (sum of squares of function values for example) you could use
an optimizing algorithm (optim, nlmin, constrOptim to name a few).
Berend
thanks for your help. I m grateful.
Eliza
Subject: Re: [R] solving simultaneous Equations in R
From: b...@xs4all.nl
Date: Wed, 11 Dec 2013 12:43:02 +0100
CC: r-help@r-project.org
To: eliza_bo...@hotmail.com
On 11-12-2013, at 12:16, eliza botto eliza_bo...@hotmail.com wrote:
Dear users of R,
I'm trying to solve the following 2 equations simultaneously in R for x
and y. I couldn't get through due to my limited knowledge of R.
3=1-[(x-1)!(2x-y-1)!/(2x-1)!(x-y-1)!]
6={[(x-y-1)!/(x-1)!]-[3(2x-y-1)!/(2x-1)!]+[2(3x-y-1)!/(3x-1)!]}/{[(x-y-1)!/(x-1)!]-[(2x-y-1)!/(2x-1)!]}
obviously, ! is factorial.
kindly help me out on it or at least suggest something.
I'll be extremely grateful.
There are several packages that solve a system of equations.
ktsolve, nleqslv, BB, which you can find in CRAN Task views: Numerical
Mathematics” and “Optimization”.
You will have to write your equations in standard R notation.
I can’t tell if your system is solvable.
Berend
Eliza
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] solving simultaneous Equations in R
Dear Berend,Got it! Thankyou very much indeed for your kind support and
elaborating the issue.I'm Extremely grateful!!! Eliza
Subject: Re: [R] solving simultaneous Equations in R
From: b...@xs4all.nl
Date: Thu, 12 Dec 2013 09:01:02 +0100
CC: r-help@r-project.org
To: eliza_bo...@hotmail.com
On 11-12-2013, at 23:56, eliza botto eliza_bo...@hotmail.com wrote:
Dear Berend,
Thankyou very much indeed for you reply. By taking help from your previous
reply @ http://r.789695.n4.nabble.com/Simultaneous-equations-td2524645.html
i was able to generate the following loop for the calculation of x=x[1] and
y=x[2].
fun - function(x) {
f - numeric(length(x))
# read as:
f[1] -
1-0.514-(gamma(1/x[1])*gamma(2/x[1]-1/x[2]))/(gamma(2/x[1])*gamma(1/x[1]-1/x[2]))
f[2] - 0.57-
(gamma(1/x[1]-1/x[2])/gamma(1/x[1])-3*gamma(2/x[1]-1/x[2])/gamma(2/x[1])+2*gamma(3/x[1]-1/x[2])/gamma(3/x[1]))/(gamma(1/x[1]-1/x[2])/gamma(1
/x[1])-gamma(2/x[1]-1/x[2])/gamma(2/x[1]))
f
}
startx - c(0.1,0.15) # start the answer search here
answers-as.data.frame(nleqslv(startx,fun))
answers
What i cant understand is the concept involved for setting startx. my
x[1] should always be smaller than x[2] and they both should be less than
1. how can i demonstrate it to startx command line?
I dont quite understand what you you mean.
Your starting values obey the restrictions you specify (if that is what you
meant).
The solution vector has all elements 1. But it is a solution.
Do you mean that you want a solution satisfying the constraints you mention?
I cannot tell if that is possible.
Generally speaking a square system of equations is solved or not.
Sometimes you can vary the starting values to get a different solution that
obeys the specified constraints.
If these constraints are necessary you are not solving a system of equations
but trying to find a parameter set that satisfies certain criteria. Together
with a criterion (sum of squares of function values for example) you could
use an optimizing algorithm (optim, nlmin, constrOptim to name a few).
Berend
thanks for your help. I m grateful.
Eliza
Subject: Re: [R] solving simultaneous Equations in R
From: b...@xs4all.nl
Date: Wed, 11 Dec 2013 12:43:02 +0100
CC: r-help@r-project.org
To: eliza_bo...@hotmail.com
On 11-12-2013, at 12:16, eliza botto eliza_bo...@hotmail.com wrote:
Dear users of R,
I'm trying to solve the following 2 equations simultaneously in R for
x and y. I couldn't get through due to my limited knowledge of R.
3=1-[(x-1)!(2x-y-1)!/(2x-1)!(x-y-1)!]
6={[(x-y-1)!/(x-1)!]-[3(2x-y-1)!/(2x-1)!]+[2(3x-y-1)!/(3x-1)!]}/{[(x-y-1)!/(x-1)!]-[(2x-y-1)!/(2x-1)!]}
obviously, ! is factorial.
kindly help me out on it or at least suggest something.
I'll be extremely grateful.
There are several packages that solve a system of equations.
ktsolve, nleqslv, BB, which you can find in CRAN Task views: Numerical
Mathematics and Optimization.
You will have to write your equations in standard R notation.
I cant tell if your system is solvable.
Berend
Eliza
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[R] solving simultaneous Equations in R
Dear users of R,
I'm trying to solve the following 2 equations simultaneously in R for x and
y. I couldn't get through due to my limited knowledge of R.
3=1-[(x-1)!(2x-y-1)!/(2x-1)!(x-y-1)!]
6={[(x-y-1)!/(x-1)!]-[3(2x-y-1)!/(2x-1)!]+[2(3x-y-1)!/(3x-1)!]}/{[(x-y-1)!/(x-1)!]-[(2x-y-1)!/(2x-1)!]}
obviously, ! is factorial.
kindly help me out on it or at least suggest something.
I'll be extremely grateful.
Eliza
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] solving simultaneous Equations in R
On 11-12-2013, at 12:16, eliza botto eliza_bo...@hotmail.com wrote:
Dear users of R,
I'm trying to solve the following 2 equations simultaneously in R for x and
y. I couldn't get through due to my limited knowledge of R.
3=1-[(x-1)!(2x-y-1)!/(2x-1)!(x-y-1)!]
6={[(x-y-1)!/(x-1)!]-[3(2x-y-1)!/(2x-1)!]+[2(3x-y-1)!/(3x-1)!]}/{[(x-y-1)!/(x-1)!]-[(2x-y-1)!/(2x-1)!]}
obviously, ! is factorial.
kindly help me out on it or at least suggest something.
I'll be extremely grateful.
There are several packages that solve a system of equations.
ktsolve, nleqslv, BB, which you can find in CRAN Task views: Numerical
Mathematics” and “Optimization”.
You will have to write your equations in standard R notation.
I can’t tell if your system is solvable.
Berend
Eliza
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] solving simultaneous Equations in R
Dear Berend,
Thankyou very much indeed for you reply. By taking help from your previous
reply @ http://r.789695.n4.nabble.com/Simultaneous-equations-td2524645.html i
was able to generate the following loop for the calculation of x=x[1] and
y=x[2].
fun - function(x) {
f -
numeric(length(x))
#
read as:
f[1] -
1-0.514-(gamma(1/x[1])*gamma(2/x[1]-1/x[2]))/(gamma(2/x[1])*gamma(1/x[1]-1/x[2]))
f[2]
- 0.57-
(gamma(1/x[1]-1/x[2])/gamma(1/x[1])-3*gamma(2/x[1]-1/x[2])/gamma(2/x[1])+2*gamma(3/x[1]-1/x[2])/gamma(3/x[1]))/(gamma(1/x[1]-1/x[2])/gamma(1
/x[1])-gamma(2/x[1]-1/x[2])/gamma(2/x[1]))
f
}
startx - c(0.1,0.15) # start the answer search here
answers-as.data.frame(nleqslv(startx,fun))
answers
What i cant understand is the concept involved for setting startx. my x[1]
should always be smaller than x[2] and they both should be less than 1. how can
i demonstrate it to startx command line?
thanks for your help. I m grateful.
Eliza
Subject: Re: [R] solving simultaneous Equations in R
From: b...@xs4all.nl
Date: Wed, 11 Dec 2013 12:43:02 +0100
CC: r-help@r-project.org
To: eliza_bo...@hotmail.com
On 11-12-2013, at 12:16, eliza botto eliza_bo...@hotmail.com wrote:
Dear users of R,
I'm trying to solve the following 2 equations simultaneously in R for x
and y. I couldn't get through due to my limited knowledge of R.
3=1-[(x-1)!(2x-y-1)!/(2x-1)!(x-y-1)!]
6={[(x-y-1)!/(x-1)!]-[3(2x-y-1)!/(2x-1)!]+[2(3x-y-1)!/(3x-1)!]}/{[(x-y-1)!/(x-1)!]-[(2x-y-1)!/(2x-1)!]}
obviously, ! is factorial.
kindly help me out on it or at least suggest something.
I'll be extremely grateful.
There are several packages that solve a system of equations.
ktsolve, nleqslv, BB, which you can find in CRAN Task views: Numerical
Mathematics and Optimization.
You will have to write your equations in standard R notation.
I cant tell if your system is solvable.
Berend
Eliza
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
