CRAMERS Rule?
Given the following twoequationstwo unknowns, write a computer program, using CRAMERS’RULE to solve for the roots.
aX + bY = C
dX + eY = f
DATA:
a b c d e f
2 5 1 2 5 5
0 3 8 .5 3 2
2 3 0 .3 0 4
Cramer's rule is used in solving linear system of equations.
Just follow up this :
http://en.wikipedia.org/wiki/Cramer%27s_rule
...
function using cramers ruleHello,
I have spent several hours trying to write a function using cramer's
rule. Unfortunatly, I can't use any short cuts or built in functions
matlab already has. It has to be a three by three matrix with inputs
A and B and out puts X1,X2,and X3. Does anyone have any samples I
could study or suggestions for me?? Thanks for any help, I'm not
looking to copy anyones work I want to learn how to do it, just needs
some guidance or direction to go in Thanks.
Steve Dunn
steve wrote:
>
>
> Hello,
>
> I have spent several hours trying to write a function using
> crame...
Transform differential equation by tranformation ruleDear Mathematica users,
I want to transform one different equation (variable r,z) to another
different equation (variable x,y).
The origin equation is :
equation = Derivative[0, 2][u][r, z] + Derivative[1, 0][u][r, z]/r +
Derivative[2, 0][u][r, z] == 0
The transform rule is :
r = Cos[x]Sinh[y]
z = Sin[x] Cosh[y]
============
Now, my task is simple, apply this transform to differential equation.
I do like this :
transformRule = {r[x][y]> Cos[x]Sinh[y], z[x][y]> Sin[x] Cosh[y]}
dtrules=Join @@ ({#,D[#,t],D[#,{t,2}]} & /@ transformRule)
But it seems that...
Vectorize Cramer's RuleHi:
I know that the Cramer's rule is quite trivial and discussed here
before. But I was looking for a solution for the general nxn case
without using any kind of loops,for,if, while commands. Just using
basic Matlab commands. I appreciate any elegant or vectorized
solutions.
"Barry yenafar" <yeknafar@yahoo.com> wrote in message
news:eeeb6af.1@webx.raydaftYaTP...
> Hi:
>
> I know that the Cramer's rule is quite trivial and discussed here
> before. But I was looking for a solution for the general nxn case
> without using any kind of loops,for,if, while c...
Use of Mathematica with Rulebased Equation DerivationsHi All  I'm a manyyear user of mathematica, but have always had one
particular problem with it that I may have just simply missed reading
about.
Mathematica Version: 5.2
Problem: I would like to develop a set of rerewite rules to apply to the
Expected Value operator. For example:
E[a x] = a E[x] a > constant, x > variable
E[b + f[x]] = b + E[f[x]] , etc.
The issue is how does one using Mathematica distinguish a 'constant
variable (i.e. a and b)' from a variable 'variable' (i.e. 'x')? The head
of a, b and x is 'Symbol' and neith...
Re: Use of Mathematica with Rulebased Equation DerivationsHi,
set up a global list of your constants and check the symbol if it is a
member of that list.
Regards
Jens
<mmorriss@gcn.ou.edu> schrieb im Newsbeitrag
news:dkfd8o$etv$1@smc.vnet.net...
 Hi All  I'm a manyyear user of mathematica,
but have always had one
 particular problem with it that I may have just
simply missed reading
 about.

 Mathematica Version: 5.2

 Problem: I would like to develop a set of
rerewite rules to apply to the
 Expected Value operator. For example:

 E[a x] = a E[x] a > constant, x > variable
 E[b + f[x]]...
Cramer's rule using LinearAlgebra package?Using the older linalg package, I could implement Cramer's rule, given
a matrix A and vector by (for example):
> A1:=copyinto(b,copy(A),1,1);
> det(A1)/det(A);
But I can't work out how to do something similar with the newer
LinearAlgebra package. For example:
> A1:=A;
> A1[1..4,1]:=b;
(for a 4x4 system). But this changes both A1 and A, so that
> Determinant(A1)/Determinant(A);
produces 1. If I assign A1:=copy(A) the same thing happens. Clearly I
want to write the vector b into a column of a copy of A, without
changing the original matrix A. S...
rule to skip other rulesWith batbook in lap, I've been trying to figure this out, but no luck
so far. I wrote this little snippet to reject all envelope recipients
that don't begin with 'foo' or 'bar'. This works great on sendmail
8.11, but on 8.12.x, with local MTA bound to 127.0.0.1, messages
destined to local user "root", "postmaster", etc., are getting
rejected.
What's the best way to say skip my ruleset below based on the sending
host (localhost)? I'm familiar with rejecting mail based on certain
conditions, but not accepting it.
FYI: I tried stuff like &quo...
Fuzzy rules reduction (49 rules to 7 rules)Hello, everybody.
(Please, excuse my bad english...)
Ok. I am working in a small software with Ada95 (on Linux) and a
PCL_812 card, to control an electric oven. I can see in some papers
and other documents the following info:
If I have (for a fuzzy controller with two inputs) 49 rules on this
way:
e(k)
NB NB NS ZE PS PM PB
NB NB NB NB NB NM NS ZE
NM NB NB NM NM NS ZE PS
NS NB NM NS NS ZE PS PM
de(k) ZE NM NM NS ZE PS PM PM
PS NM NS ZE PS PS PM PB
PM NS ZE PS PM PM PB PB
PB ZE PS PM PB PB PB...
equation numbering for multipart equationHow can I get separate equation numbering for equations like in "cases"
environment?
For example:
\begin{equation}
f(x)=\begin{cases}
\frac{1}{2} \\
x^2 \\
1
\end{cases}
\end{equation}
should look like
1/2 (1.1)
f(x) = { x^2 (1.2)
1 (1.3)
The lines in my real problem are quite complicated and have different
heights.
Further, I would like to be able to refer to the labels, and the labels
should align at the right margin of the text, just like with usual
equation numbers.
Any help appreciated!...
Equation numbers only on referenced equationsHello,
When I typeset a document with equations, I like that only those
equations that are referenced somewher in the text are numbered. Is
there any way to do that automagically, from the \ref{} tags found,
instead of having to manually change equation for equation*?
I've searched the web extensively, but haven't found any clue.
Thanks in advance,
V=EDctor
V�ctor Zabalza wrote:
> Hello,
>
> When I typeset a document with equations, I like that only those
> equations that are referenced somewher in the text are numbered. Is
> there any way to do that automagically...
Scaling equations/Spacing in equationsHello,
I have two different problems with equations in latex.
First I would like to scale some of my equations. Everything I tried,
caused the numbering to be scaled. I found no way to suppress the
scaling of numbering. (I tried to set the size by the fontsize command
and with a scalebox). How can I scale my equation without scaling the
numbering?
The second problem is the space between the variables. Currently I'm
using \; to define spacing between two variables. Does someone know a
good solution to solve this problem without using a spacing command by
a global setting or special rules t...
use equations out of list of equationsHello,
I have solved a system of equations in MuPAD with linsolve, and as result I get a list of equations e.g.
[a = c/2 + d/2, b =  c/2  d/2].
I am able to index the list and get the single entries (equations) e.g.
a = c/2 + d/2
but I cannot use them for my next calculation steps.
Is there a way to get only the right hand side of these equations, that I can use them for further calculations?
Thank you for your help.
"Marcus " <lrt49861@stud.unistuttgart.de> wrote in message <hdtilc$inf$1@fred.mathworks.com>...
> Hello,
>
> I have solved a system of equa...
Excel equation to Access EquationIs the any way to convert an equation in Excel to something Access will
understand other than manually rewriting the code?
Basic equation has several *MOD(A,B) and several IF(AND(C,D)...
simply changing MOD(A,B) to (A MOB B) and changing
IF(AND(C,D)... to IIF(C AND D)... does not do the trick. I suspect I'm having
parentheses problems. A, B, C, and D are themselves complex equations.
Chuck
On Thu, 07 Jun 2007 13:56:16 0400, Chuck <libbeyc@schoollink.net>
wrote:
No, you're on your own.
Tom.
>Is the any way to convert an equation in Excel to something Access will
>un...
Very simple number equation does not equate.Dear matlab gurus,
I encountered a very puzzling problem. 0.2+0.2+0.2+0.15+0.05 clearly adds up
to 0.8. But on matlab R2007b, it does not equate. Why? I have been tearing
my hair apart as this problem looks so simple and yet elusive. Could some
matlab guru enlighten a newbie like me?
Below are what appears on my matlab screen;
>> 0.2+0.2+0.2+0.15+0.05==0.8
ans =
0
>> 0.2+0.2+0.2+0.14+0.06==0.8
ans =
1
>> 0.2+0.2+0.2+0.2==0.8
ans =
1
"sun" <sun@gmail.com> wrote in message <h2qav3$7um$1@reader01.singnet.com.sg>...
> Dear ma...
RuleI got surprised when I saw that my Mathematica 7 computed
FourierTransform[DiracComb[t], t, f] without trouble but couldn't deal
with
FourierTransform[DiracComb[2 t], t, f]
So I thought about writing a rule that uses the property that the
F{x[k t]}[f] = 1/k F{x[t]}[f/k] (I think :P)
In Mathematica's words:
FourierTransform[ expr_ , t_, f_] should be transformed, only if in
"expr" you can find aall "t"s multiplied by the same thing (let's call
it "k"), and that thing doesn't have "t"s inside, into
1/Abs[k] FourierTrnasfor...
RuleHi,
How to create a rule which when an insert appears, update another row in
another table with the value of the insert.
for exemple :
Table myins(col10,col11,col12)
Table myupd(col20,col21,col22)
When : Insert into myins(col10,col11,col12)VALUES(1,2,3);
I want : update myupd set col21=col11, col22=col12 WHERE col20=col10;
but if I write this rule like this :
CREATE RULE regle1 AS
ON INSERT TO myins DO update
SET col21=NEW.col11, col22=NEW.col12
WHERE col20=NEW.col10;
and i write Insert into myins(col10,col11,col12)VALUES(1,2,3);
This rule update all the r...
spacing etc. with equations and equation arraysHello all,
I'm a little frustrated by two things in Latex, and I haven't been able
to figure out how to deal with them by looking online.
1) I would like to be able to leave a blank line in the code before and
after equations. That makes it much easier to find things when I'm
looking for them during editing. The trouble is that when I do that it
inserts spaces in the DVI file as well, or indents the following line
so that it looks like the start of a new paragraph.
2) When I use the equation arrays, the lines are often very strangely
lined up, and it looks bad. For instance, the...
difference equations to solve wave equationi am new in matlab. Can any one help out in how to solve a the wave equation using finite difference methods(Say the five point method). I will be grateful. Thanks
On May 13, 3:42=A0pm, "Kayanja Andy" <kayanja.and...@yahoo.com> wrote:
> i am new in matlab. Can any one help out in how to solve a the wave equat=
ion using finite difference methods(Say the five point method). I will be g=
rateful. Thanks
what have YOU done so far to solve YOUR particular problem...
us
"Kayanja Andy" <kayanja.andrew@yahoo.com> wrote in message
news:hsgvjc$c11$1@f...
replace one rule in a list of rulesI have a list of simple rules. I want to repeatedly replace one of
them. Is the best way to simply prepend the new rules, or is there a
"prettier" approach?
Thanks,
Alan Isaac
On Mar 17, 12:54 am, Kathryn Isaac <kathryn.is...@gmail.com> wrote:
> I have a list of simple rules. I want to repeatedly replace one of
> them. Is the best way to simply prepend the new rules, or is there
> a "prettier" approach?
>
> Thanks,
> Alan Isaac
If all you want to change is the righthand side of the rule
then use RuleDelayed with a dummy righth...
Abbreviations for begin{equation} ... end{equation}Is it OK to define the abbreviations
\newcommand{\beq}{\begin{equation}}
\newcommand{\eeq}{\end{equation}}
to save some typing ? And can \def be used in lieu of \newcommand?
Thanks
carlos.felippa%colorado.edu@gtempaccount.com wrote:
> Is it OK to define the abbreviations
>
> \newcommand{\beq}{\begin{equation}}
> \newcommand{\eeq}{\end{equation}}
>
> to save some typing ? And can \def be used in lieu of \newcommand?
Why not try it? If it works you may use it. If not, and you don't understand
why not, post a minimal complete example with the e...
Single equation number for system of equationsHello,
I have a system of equations (actually several of them) of the form
\begin{align}
a &= b \\
c &= d \\
e &= f \\
g &= h,
\end{align}
I would like to use a single equation number for the complete system. I
was wondering if there is an environment similar to align that will have
a single equation number that is centred automatically. (The solutions I
found by searching suggest using \notag after some of the lines in
align, but this is a bit inconvenient and doesn't make it possible to
centre the equation number when there are an even number of equations.)
Szab...
How to plot equations like this equation in matlab?Hi
I want to know how I can plot some equation like this equation like
this:
x^3+ zyx^2+z^2yx+y^2xz+xyz+y^3+z^3=0
By and large how I can plot equation without parametrization in
matlab.
Thanks.
"F.Vesali" <farshad.vesaly@gmail.com> wrote in message <ad9781297f904685b8d9dc536dc63a31@r24g2000yqd.googlegroups.com>...
> Hi
> I want to know how I can plot some equation like this equation like
> this:
> x^3+ zyx^2+z^2yx+y^2xz+xyz+y^3+z^3=0
> By and large how I can plot equation without parametrization in
> matlab.
> Thanks.
a hint:
help ezplot; ...
Equation number to left side of the equationHi all, i wanted to do the following with (6) in the same line as the
rest.
How on earth is that done?
\setcounter{tmp1}{6}
\begin{list}{(\arabic{tmp1}) }
\item \begin{eqnarray*}
\rho r(S \backslash A^{\star}) & = & S  A^{\star}  \rho ^{\star}
S + \rho ^{\star} (A^{\star})\\
& = & S  \rho ^{\star} S = \rho S.
\end{eqnarray*}
\end{list}
Btw, im a complete noob in latex so a ready text to copy/paste is the
only way you can help me :/
Thx a lot in advance!!!
Xew
if you don't want to hack latex, I think it's easier to just use
amsmath package
a...
tabular, hrule, vertical rule and no ruleI am sure I have done this before but I can't seem to remember a
simple way.
I want a square table. Row one and column one have no rules, just
text. Cell (1,1) is blank.
Cells (2,2) (nn) have both vertical and horizontal rules separating
them.
For use in contingency tables, payoff matrices, and so forth.
I can't remember how to get vertical rules in some rows and not
others.
Or alternatively the vertical rule to the left of column two extends
up through row one and the horizontal rule above row two extends to
the left through column one.
I am drawing a blank.
In article <...