Create a loop to divide number and distribute half in the positive direction and half in the negative direction.

Take a number and divide it in half then distribute it evenly along z axis (1 meter apart). I am working on a project for school where I have to calculate e-field at a point based on multiple charges being evenly spaced along z-axis. Say I have 101 charges... I would have a 50 charges in the positive z direction and 50 charges in the negative direction as well as a charge at 0,0,0.

I believe I now how to do all of the calculating part of this project but my trouble is formulating a loop that will do what I describe above. Any help would be greatly appreciated.

[John D'Errico]

No. This is not a question of formulating a loop. A loop is just a, well, a loop. Computer statements are not a model. In fact, they mean nothing without the context of a model behind them. So don't look at this as a programming problem, YET.

This is really a question of thinking about how to model the problem.

[Image Analyst]

Hint: Take a look at the linspace() function.

[Star Strider]

Are the charges:

1. fixed in amplitude (constant values, or integer multiples of the electron charge, for example),
2. randomly distributed in space (although always one metre apart) [0 + - - + + + - + ...],
3. simply alternating in direction [0 + - + - ...],
4. some combination of these?

Details are important!

[Image Analyst]

He says the charges are "evenly spaced along z-axis"

[sanbadgerdude]

Actually what I want to do is take a vector [x y z] and use it in an equation and once i have evaluated that equation increment z by 1 and evaluate equation again

[John D'Errico]

If you KNOW what you want to do, then surely this will suffice?

for z = -50:1:50
  ...

[Star Strider]

O.K.

We’re slowly uncovering the mystery here.

Does your function calculate the current value for z as a function of the previous values of it at the previous values of z, or is it independent of the function values at previous values of z, and only dependent on the current value of z?

We could be here for hours (or days) discovering what you want to do, or you could just tell us.

I’m cool with either option.

You choose!

Answer 1

[John D'Errico]

I think you are making the problem more complex than it need be, but at the same time, you are wanting to create code too quickly to represent a system that you have not really though out how it will act. The code should come only after you understand how you will formulate the model. Once you have that understanding, the code usually is trivial to write.

For example, it sounds as if your problem is to create a set of 101 point charges, which are then used to approximate a continuous charge distribution.

In that case, then all you need to know are the locations of those charges, and the strength of those charges. Then you can compute the effect of each charge on the electric field at some other point, thus summing their individual impacts.