Linear equation solution
in [Matlab]
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From: Abhishek on 14 Jul 2010 09:11 Hi I am working on an LDO circuit which i have to model using Kirchoffs in MALAB. But I am getting 13 equations with nearly 70 variables.\ Malab crashes in solving those equations . Please tell me a solution to this problem......
From: John D'Errico on 14 Jul 2010 09:30 "Abhishek " <abhi14jan(a)yahoo.com> wrote in message <i1kd19$1sb$1(a)fred.mathworks.com>... > Hi > I am working on an LDO circuit which i have to model using Kirchoffs in MALAB. > But I am getting 13 equations with nearly 70 variables.\ > Malab crashes in solving those equations . > > Please tell me a solution to this problem...... You called this a linear system. Even if the problem is linear with constant, known coefficients, there is no unique solution. It sounds like you have symbolic coefficients though. A symbolic problem with 13 equations and 70 unknowns will still have no solution. Wanting to do something badly enough does not make it doable. John
From: Steven Lord on 14 Jul 2010 09:32 "Abhishek " <abhi14jan(a)yahoo.com> wrote in message news:i1kd19$1sb$1(a)fred.mathworks.com... > Hi > I am working on an LDO circuit which i have to model using Kirchoffs in > MALAB. But I am getting 13 equations with nearly 70 variables.\ > Malab crashes in solving those equations . > > Please tell me a solution to this problem...... If MATLAB is actually _crashing_ (i.e. creating a crash log file and asking you to exit MATLAB) then you should follow the instructions given at the bottom of the log file. If MATLAB is simply _erroring_ then post the COMPLETE text of the error message you receive as well as a SMALL snippet of code from the location where the error occurs as well as information (from WHOS, for a start) about the variables that exist when that line of code executes. -- Steve Lord slord(a)mathworks.com comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ To contact Technical Support use the Contact Us link on http://www.mathworks.com
From: Abhishek on 14 Jul 2010 09:48 "Steven Lord" <slord(a)mathworks.com> wrote in message <i1ke8l$mf8$1(a)fred.mathworks.com>... > > "Abhishek " <abhi14jan(a)yahoo.com> wrote in message > news:i1kd19$1sb$1(a)fred.mathworks.com... > > Hi > > I am working on an LDO circuit which i have to model using Kirchoffs in > > MALAB. But I am getting 13 equations with nearly 70 variables.\ > > Malab crashes in solving those equations . > > > > Please tell me a solution to this problem...... > > If MATLAB is actually _crashing_ (i.e. creating a crash log file and asking > you to exit MATLAB) then you should follow the instructions given at the > bottom of the log file. > > If MATLAB is simply _erroring_ then post the COMPLETE text of the error > message you receive as well as a SMALL snippet of code from the location > where the error occurs as well as information (from WHOS, for a start) about > the variables that exist when that line of code executes. > > -- > Steve Lord > slord(a)mathworks.com > comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ > To contact Technical Support use the Contact Us link on > http://www.mathworks.com > hey, the matlab crashes means it closes as soon as i run the code......
From: Abhishek on 14 Jul 2010 10:01
"John D'Errico" <woodchips(a)rochester.rr.com> wrote in message <i1ke62$h35$1(a)fred.mathworks.com>... > "Abhishek " <abhi14jan(a)yahoo.com> wrote in message <i1kd19$1sb$1(a)fred.mathworks.com>... > > Hi > > I am working on an LDO circuit which i have to model using Kirchoffs in MALAB. > > But I am getting 13 equations with nearly 70 variables.\ > > Malab crashes in solving those equations . > > > > Please tell me a solution to this problem...... > > You called this a linear system. Even if the problem > is linear with constant, known coefficients, there is no > unique solution. It sounds like you have symbolic > coefficients though. A symbolic problem with 13 > equations and 70 unknowns will still have no solution. > > Wanting to do something badly enough does not > make it doable. > > John >no u are not understanding ,there are 13 equations with 13 unknowns >the equations include parameters of the ckt of bjt and mosfet which i have to substitute later..... >but matlab does not even calculates the transfer function it just closes >can u help me please... |