Recent content by yashar

  1. Y

    Graduate What Are the Key Differences Between Quantum and Classical Correlation?

    i want to know what is physical idea behind "correlation function" as you know in quantum we define <B(t)B(s)> , B(t) and B(s) are operators in different time. and angular bracket shows averaging. is this definition say that if correlation function does not vanish then the observables...
  2. Y

    Graduate What Are the Key Differences Between Quantum and Classical Correlation?

    hi i want to know that what is quantum and classical correlation. is there any book or paper? thanks
  3. Y

    Mathematica How to Plot Large Data Sets in Mathematica?

    hi i upload the data.txt file . how to plot it? i tried ListPlot but it did not work thanks
  4. Y

    Mathematica How to Plot Large Data Sets in Mathematica?

    hi i compile a c++ program and after compiling it gives me a txt file which contains about 50000 points. how i can plot these points in mathematica? thanks
  5. Y

    Mathematica Problem in NDSolve in mathematica

    i can not understand how did you do that. please tell me how?
  6. Y

    Mathematica Problem in NDSolve in mathematica

    thanks that was amazing! how you guess that?
  7. Y

    Mathematica Problem in NDSolve in mathematica

    i want to solve a large system of coupled differential equations but i get this error NDSolve::nlnum: i attach the notebook in zip format. what is the problem? thanks
  8. Y

    Mathematica Integro-Differential Equation with mathematica

    hi how can i solve a system of Integro-Differential Equations in mathematica numerically or analytically? thanks
  9. Y

    Mathematica How to define local variables and constants in mathematica

    thanks
  10. Y

    Mathematica How to define local variables and constants in mathematica

    hi suppose i run Two notebook and in each of them i have matrix A and Constant B and a function C in each notebook these things have the same name. if in notebook 1 i assign B=10 then in notebook 2 B is 10 too , which is not my desire. how can i define these constants and matrices and...
  11. Y

    Mathematica Running simultaneous computation in mathematica

    Bill Simpson thanks for your comments. jackmell i do not know how to do that. however i think i should define the results of computation in new variables. for example if after a computation i obtain a matrix i define it for another variable.
  12. Y

    Mathematica Running simultaneous computation in mathematica

    hi when i run a heavy computation on mathematica in the same time even if i want to calculate 2+2 , mathematica does not calculate it until calculating of heavy computation finishes. why? another problem is that when i do a heavy computation and obtain results , after closing mathematica...
  13. Y

    Mathematica Problem with superscript and subscript in mathematica

    hi i want to sum over two indices i and j . the elemet that i must sum is (x^(i,j))-i that is x has superscript i,j and subscript i. but in mathematica it gives me error. here is the notebook : http://www.mediafire.com/?novtz7t0liu9u78 thanks (:
  14. Y

    Mathematica How to Plot x[t] Versus y[t] in Mathematica?

    hi i solve numerically two coupled equation and obtain two function x[t] and y[t]. how i plot x[t] versus y[t] so that horizontal axis to be x[t] and vertical axis to be y[t]. here is the notebook of mathematica http://www.mediafire.com/?g4sa3zi630vi8nl thanks
  15. Y

    Graduate ODE System with Variable Coefficients

    hi in this article that explain the method of peani baker http://arxiv.org/pdf/1011.1775v1 i can not understand how in page 5 for first example it calculate element (1,2) of I(t)(with subscript n) can anybody help?