Login
Password
Sources on this Page

> Headlines by Category

 Home / Science / Mathematics

You are using the plain HTML view, switch to advanced view for a more complete experience.

xticks displayed in datetick
Hi,
I want to make a plot with x-variable being time in numeric format. Now I want to display the xtick as HH:MM, with start and end as 10:00 and 14:00 and time step as 1h. I use the cods as below, it works incorrectly (the result is wrong e.g. it displays 10:30 not 10:00 and the time 10:30 is displayed in the wrong position), but no error message. Could you help me? Thanks a lot!

f4=plot(time,y);
datetick('x','HH:MM');
xmin=datenum([2015 7 24 10 0 0]); % start time: yyyy mm dd HH:MM:SS
xmax=datenum([2015 7 24 14 0 0]); % end time: yyyy mm dd HH:MM:SS
step_1h=datenum([0 0 0 1 0 0]);
set(gca,'xtick',[xmin:step_1h:xmax]);
Re: Objective function: residuals scaled by the nominal value of the
Euh <EuhNgroups@hotmail.ca> wrote in message <f3fec143-4bb4-44e0-b918-270d5776b48f@googlegroups.com>...
> For fitting a model with least-squares optimization, I have always used a variance weighted sum of squared residuals as the objective function.
>
> If someone is instead scaling the sum of sqaured residuals by the nominal values of the variables, i.e.:
>
> sum((X_experimental - X_measured)^2/(X_measured)^2)
>
> X being a bunch of different measurements with (most likely) different associated errors.
>
> What could be the incentive for such an objective function ?
>
Put in the simplest of terms: That gives you the correctly weighted fit iff the measurement uncertainty is proportional to the measured amplitude (sigma_X = C*X_measured). Goodness-of-fit and so on just proceeds with that in mind.
Re: simulink stepsize problem
Hello,
 
I had the same problem and eliminated it by decreasing the rel tolerance in the solver panel which can be seen under model configuration parameters when you right click on your simulink page. But the accuracy reduces when you do so.
How to adjust B-H curve of saturable transformer
Anyone please suggest me here how to plot B-H curve in simulink of a transformer at no load.
We are just having source and transformer no other data is available.
I also want to adjust its width so pls help me out
Problems on matrix dimension in matlab
Given the original model as:
R = (Enp(1-p)r_SR r_RD)/((1-p)(E+n^2 p^2 r_RD?f|^2 ) r_SR+E(E+npr_RD)); and
E=1-np|f|^2

For matlab script written by me:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
E = (1-eta.*rh.*f2);
r_xx = (E*eta.*rh.*(1-rh)*r_sr*r_rd') / ((1-rh)*(E+(eta^2.*rh.^2*r_rd.*f2))*(r_sr) +(E)*(E+eta.*rh.*r_rd));

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
where
r_xx = RR / (A *(E+RD)* B + E* RG
size(RR) = 15 1
size(A) = 15 1
size(E) = 15 1
size(RD) = 15 26
size (B) = 1 26
size(RG) =

Question 1.
>> E +RD
Error using +
Matrix dimensions must agree.
       Please how can I solve this problem

Question 2. The comment for RG
>> RG
Error using .*
Matrix dimensions must agree.
    How can I solve this problem after trying using *
Question 3.
     Please Guide me on how to get r_xx correctly.
Dynamic link library failure
Hi,

Up until a few days ago, MATLAB was working perfectly fine on my computer and has been since I installed it a couple of months ago. Now, whenever I try to run any script, it will say it's busy for about a minute and then I get the following error:

"Error using patch
Can't load 'C:Program FilesMATLABR2016abinwin64handle_graphics.dll': A dynamic link library (DLL) initialization routine failed."

I have checked and the file exists. Any help would be appreciated.


Juan
Re: How can I get the pixel values of ROI chosen with imellipse?
Adva BM" wrote in message <herfe9$phf$1@fred.mathworks.com>...
> Hi,
> I would like to calculate the mean pixel value of an ellipse ROI chosen by the user in an image (using imellipse) . What is the shortest way to know which pixels were chosen, or what is their value?
> For a rectangle it is easy, but what about an ellipse?
> Thanks!

Hi Adva,
I am a MatLab newbie, and since you mention that determining the mean pixel value of a rectangle is easy, I was wondering how you do it?
Thanks!!
Rebecka
Re: Meijer-G function .m file
Akarsh Pokkunuru" <akarsh.28891@gmail.com> wrote in message <npfkau$ic4$1@newscl01ah.mathworks.com>...
> "Nasser M. Abbasi" wrote in message <np69sf$15b2$1@gioia.aioe.org>...
> > On 8/18/2016 11:39 AM, Akarsh Sundareswar Pokkunuru wrote:
> >
> > >
> > > I have a similar question regarding Meijer G function. I would
> > >really appreciate your advice on this topic.
> > > I have the G-function representation of the form given below -
> > >
> > > summation " i " from 0 to infinity
> > > G(3,1,2,3) [ k+1/v | -1-i, -i, 0, -1-i, -1-i ]
> > >
> > > Here, the summation variable " i " varies from 0 to infinity inside
> > >the G function and also k and v are real numbers.
> > >
> > > How do i express the above function using matlab code?
> > > Hope you can provide some advice.
> > >
> > > Thank you,
> > > Akarsh
> > >
> >
> > I am not able to parse your question correctly. I do not understand
> > what
> >
> > > summation " i " from 0 to infinity
> > > G(3,1,2,3) [ k+1/v | -1-i, -i, 0, -1-i, -1-i ]
> >
> > means. I do not understand the notation used. sorry.
> >
> > --Nasser
>
> Hello Mr. Nasser
>
> Thank you for the immediate reply. Please click on the link below -
>
> http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=1388718
>
> The Meijers G function I am referring to is in equation (5). I am trying to plot the equation (5) using matlab.
>
> Thank you,
>
> Akarsh


Hello Mr. Nasser

The above paper used Wolfram mathematica to write that function and that is why the notation is a bit different.
Anyway this is the expression closest to what I could write in mupad interface for the above Meijers G function -

sum(meijerG([[],[-1-n,-n]], [[0],[-1-n,-1-n]],(k-1)/v), n=0..infinity)

(K - 1)/v is an array of values which will be plugged into the above expression.

However its a bit different from the equation in paper. What is the mistake I am doing?

Thank you
Re: Matlab. symbolic mathematics
Nasser M. Abbasi" wrote in message <jn882h$rlr$1@speranza.aioe.org>...
> On 4/25/2012 12:23 AM, Eli Holowatch wrote:
> > f3=sym('cos(2x)*sin(x)')
> > Error using sym>convertExpression (line 2576)
> > Conversion to 'sym' returned the MuPAD error:
> > Error: Unexpected 'identifier' [line 1, col 6]
> >
> > Error in sym>convertChar (line 2487)
> > s = convertExpression(x);
> >
> > Error in sym>convertCharWithOption (line 2470)
> > s = convertChar(x);
> >
> > Error in sym>tomupad (line 2224)
> > S = convertCharWithOption(x,a);
> >
> > Error in sym (line 111)
> > S.s = tomupad(x,'');
> > Why an i getting this error message back?
>
> cos(2x)*sin(x) is NOT a symbol. It is an expression that
> contains a symbol.
>
> In the above 'x' is the symbol.
>
> Hence, just do
>
> EDU>> syms x
> EDU>> f3=cos(2*x)*sin(x)
>
> f3 =
>
> cos(2*x)*sin(x)
>
>
> --Nasser

Hello Mr. Nasser

The above paper used Wolfram mathematica to write that function and that is why the notation is a bit different.
Anyway this is the expression closest to what I could write in mupad interface for the above Meijers G function -

sum(meijerG([[],[-1-n,-n]], [[0],[-1-n,-1-n]],(k-1)/v), n=0..infinity)

(K - 1)/v is an array of values which will be plugged into the above expression.

However its a bit different from the equation in paper. What is the mistake I am doing?

Thank you
Un planeta similar a la Tierra orbita en torno a la estrella más cercana al Sol
Después de mucho buscar, un equipo internacional de astrónomos liderado por científicos españoles ha encontrado el exoplaneta más cercano a la Tierra. Se llama Próxima b, su masa es parecida a la del nuestro, gira cada once días alrededor de la vecina estrella Próxima Centauri y está situado en la zona de habitabilidad, es decir, que podría albergar agua líquida y, potencialmente, vida.
Post Selected Items to:

Showing 10 items of 893

home  •   advertising  •   terms of service  •   privacy  •   about us  •   contact us  •   press release design by Popshop •   Official PR partner PRNews.io •   © 1999-2016 NewsKnowledge