Recent content by gluons

I think I may be able to construct a different integrand if I parameterize the problem differently...will check back later.

The integrand is of the form $$\int d\theta \sin2\theta \sqrt{\alpha^2 - (r-\beta\tan\theta)^2}$$ Completing the square will simplify the radical, but the radicand becomes negative in this case: $$\int d\theta \sin2\theta \sqrt{-\gamma-u^2}$$ where $$u=\tan\theta-r/\beta$$ and...

I have constructed a formula to represent the neutron flux from a disc emitter through an aperture. I have got it down to a double integral of a form that I can't see how to evaluate. Mathematica crashes on this and I am not ready yet to give up and go to numerical solution. Does anyone know a...

I am writing a code to calculate and to operations with a large set of matrix elements, indexed by four numbers. I am also writing these subroutines within a much larger code structure, so I do not have total freedom to modify the objects I am using. I am trying something like this, which...

Flush is working. Awesome command, thank you!

So it turns out that this does in fact write to file, but only after the entire program is finished completing. How can I ask it to perform these writes individually?

The code creates the file just fine. I can change the name of the file if I want to. It just won't write anything to it. I get no compile or run errors either, just nothing being written to file. open(unit=2,file="test.OUT") I run from terminal.

I've never had this issue before. My code will create the file and also output anything to terminal. But if I change the output from terminal to file, it does nothing. For example, this line write(*,*) "ist1, ist2 =",ist1,ist2 outputs my two indices in every loop iteration. But...

I am writing some code which involves numerical integration of a function on a 3D grid of points. I am defining the type vector to refer to these points, and I am also trying to extend the intrinsic operator * to include scalar and vector multiplication. However, I cannot compile and I don't...

Thank you!

I am working on a problem to evaluate integrals with simple poles offset by ε above/below the real axis. So something like this ∫ [ f(x) / (x-x0-iε) ] The answer is the sum of two integrals: the principal value of the integral with ε=0 plus the integral of iπδ(x-x0). I have done the...

Hello, I am looking for a good reference book that has a detailed derivation of the single particle Green's function. I expected this to be in Sakurai but it's not. I couldn't find the spectral representation of this simple function in Ashcroft or any other solid state book either. Jackson...

Thank you! The binomial test was just what I was looking for.

I am not sure how to answer the following question, which I have posed to myself to better understand the method: "Suppose two six-sided dice are rolled together N times. What is the uncertainty in the number of times any given total appears on the dice?" For example, what is the...