Recent content by tomyuey938

no match?? I've neither experience with g77 nor Mountain Lion, so I might not be much help, but one thing is not clear: why do you get a g77 "no match"? What happens when you run g77 with the full path (ie, /dir/to/g77 hello.f [...])?

Yes, eventually it will turn to solid (assuming your temperature doesn't change). Find your temperature / pressure on this phase diagram [1] then track upwards as you increase the pressure at constant temperature. It will eventually turn to ice as the molecules are forced together, though the...

My guesses would either be that you're going beyond the allocated range of your arrays (DF seems a possible candidate) or that you're dividing by zero or taking the log of a non-positive number. Also, you're still mixing integers and reals (eg, at "1.0/n", etc) which might cause values to be...

Great. Try putting in some lines like print *, "a" print *, "b" etc after each part of the code to see where it's getting stuck. Then when you know which loop is causing the problem, print out important numbers like print *, "n= ", n inside the loop. This should allow you to determine...

Hello. You need to define "n" before "DO WHILE (n < 10)". Also, n is not incremented in that loop. Be careful not to mix integers and reals. For example, "n_factorial * i" is a real times an integer. "real(i)" will be better. The same for 1/n_factorial (try "1./n_factorial") Finally, check...

cgk, edguy99, thanks for your replies. As I was looking for the best place to obtain information about the crystal structure codes and how to calculate co-ordinates based on them, I came across this website: http://cst-www.nrl.navy.mil/lattice/pearson/index.html It seems to have a...

Thanks for your kind suggestion! I appreciate your suggestion a lot, but I'm not sure it matches the requirements closely enough (and it's old: System requirements are Windows 9x or NT !). I'll check it out in more detail if I can hold of a computer with windows on, but meanwhile, can...

Hello, Does anyone know any (free) software for generating simple crystal structures like forms of SiO2 or TiO2? It must be a really common problem. My current strategy is to search the web for hours until I get lucky. There are online databases which have really complicated structures from...

dot.hack, thank you so much, I've got it now. I made such a trivial mistake. I really appreciate your help!

This is from self-study coursework rather than homework. I hope it's ok in this forum. I'm following a statistical mechanics lecture on youtube, and the professor is deriving the average energy as a function of the partition function. He goes: -1/Z dZ(beta)/d beta = -dlnZ(beta) / d beta where...

Hi Starstrider, Thanks for your reply. So in order to get an expression for v(t), I simply differentiate both sides by t to give: dL/dt = SQRT(2A/B) (1/2) t^(-1/2) Thanks also for the "self-consistent" term. This will be helpful in the future. Thank you both so much for your help. I really...

Hi tiny-tim, Thanks for your reply. Well, I'm trying to calculate the value of v(t) at a given value of (t). So I don't think your re-arrangement is relevant in this case, since I need v(t)=something. But I don't know the value of L, since L is the integral of v(t) dt up to that time (t)...

Hi, I'm calculating the velocity of something that's stretching, and as it gets longer, the velocity decreases. So to calculate the velocity at time (t): v(t) = A / (B L(t)) A change in the distance over a small time dt will be given by: dL=v(t) dt So I guess the distance is: L=...

Hi, I have the following expression: d(v+(dv/dr)dr)/dr and somehow it can be converted to read as: (dv/dr) + (d^2v/dr^2)dr but I can't for the life of me figure out how to get from the first expression to the second expression. I've tried looking at the product rule, cancelling...