Recent content by ngendler

Also, in any case the electric field must be different! Without the retarded time, the electric field around a charge that appears is there instantaneously--with it, there is no electric field for a short amount of time.

But my computer simulation doesn't know about the electric field generated by the magnetic field... All it knows is that E=q \vec{r}/ r^3

Ah, okay! Thanks.

It's not cause and effect, but it certainly changes what the field looks like at any given time... Can you explain why my circling charge has a component of the field in the direction of motion?

That makes sense. However, in the case of, say, a charge moving in a circle--taking into consideration the retarded time points part of the electric field in the direction of motion at any given moment. Doesn't this add a curl to the field?

I am thinking about the curl of the electric field and want to make sure I have something straight: Say you have a charged particle moving along some prescribed path. The electric field propagates outward at speed c, leading to a "retarded" time that you need to calculate in order to get the...

Nevermind, I figured it out. I just included the file as < file.txt > in the command line where I ran the program.

@jtbell, thank you but no. I'm not trying read files within the program. The program is all completely written. But now when I run it, I think I need to link to those files or something, I'm not sure.

Hi, I am trying to run a simulation written mostly in Fortran on Linux. The User's Manual says that "To run a simulation one needs to read several input files." Then, it lists a bunch of files. I was wondering what it means by that and how I "read" the files? Thanks in advance, Naomi

@Borek, yes I am sure. I want the user to be able to say "x**2" and have the program read it and integrate it.

Hi! I'm trying to write a function that will integrate a user given function. I am having trouble with reading the function. Here is a section of my code: [FONT="Courier New"]function f(x) implicit none real :: x,f,p print *,'Type a probability density function' read *, p !It doesn't...

@SteamKing, that didn't work. When I remove f from my list of reals, I get another error saying that f has no implicit type, which makes me think that I need it to be declared as real.

Thank you, @SteamKing! It worked!

Getting an "unclassifiable statement" error in Fortran 95 I am trying to integrate the function x from 0 to 1. Here is my code: [FONT="Courier New"]program myownmonte !This program will integrate the function x from 0 to 1 implicit none real :: ans0,y,f,x,xmax integer ...

I am trying to write a program that in Fortran 95 will integrate x^2 from 0 to 1. Easy right?? I'm getting errors, though, that I really don't understand. Here is my code: [FONT="Courier New"]program montecarlo2 implicit none real :: fmax,iseed,srand,xmax,x2,x,y !why do we need pi...