38,207 reputation
156151
bio website uoregon.edu/~noeckel
location
age
visits member for 2 years, 2 months
seen 6 hours ago

18h
awarded  Guru
20h
comment Manipulate for Electric Field
You definitely should write your code as a Module, making sure to end lines with ;. Once you've wrapped it inside a function with all variables localized, the displacement of the charge can be introduced as a function parameter.
20h
comment Manipulate for Electric Field
The code you have is pretty slow, but fortunately the interactivity you are looking for is also very easily realizable by simply pre-rendering a Table of plots in which the charge location is varied step-wise. That list of images can then be quickly manipulated, most easily by using ListAnimate.
20h
comment Little triangles appearing in a Mathematica region plot saved in a PDF file
If you don't want to convert to a rasterized format, then the solution to Avoiding grid lines inside filled area in RegionPlot exported as PDF appears to work fine here. That's why I would consider this a duplicate of the question linked here or in the above comment by @Steve D.
1d
comment Solving for a charge distribution from a dipole moment
This question appears to be off-topic because it is about a physics concept without which the mathematical problem is ambiguous.
1d
comment Solving for a charge distribution from a dipole moment
I can guess the result you're supposed to arrive at (it involves the divergence of $\bar{p}$), but it's not a Mathematica problem. It's a physics problem.
1d
comment Solving for a charge distribution from a dipole moment
And now what's missing are some properties of the function $\rho$ because it is probably a "moving average" of the charge density. Otherwise it wouldn't have two vector arguments but one. Not knowing these properties, there is too much arbitrariness in the problem.
1d
comment Solving for a charge distribution from a dipole moment
As it is written right now, your question is too general for the context of a Mathematica forum because you are presenting only a formal integral definition and then hint at the fact that the charge distribution is induced by an applied electric field. If you are indeed facing an integral equation, then you have to be more specific about what you have already tried in Mathematica, maybe giving a specific form of the field.
1d
comment Why does Arrow not work well with Scaled coordinates in 3D?
@gpap That's a great example, very entertaining... somebody at Wolfram really should re-think the way arrows wok in 3D. This internal use of Scaled for the heads causes so much headache.
2d
answered ContourPlot refuses to show in-figure PlotLegends after turn on ContourShading
2d
revised Why does Arrow not work well with Scaled coordinates in 3D?
Removed unnecessary Graphics
2d
comment Why does Arrow not work well with Scaled coordinates in 3D?
@gpap I just added an answer - my own approach was simply to avoid scaled coordinates as much as possible...
2d
answered Why does Arrow not work well with Scaled coordinates in 3D?
2d
comment Why does Arrow not work well with Scaled coordinates in 3D?
I think this is closely related to an issue I addressed on my web page some time ago. I agree with @Kuba that it's not expected behavior. If you want, I could post the arrow function from my web site as an answer...
2d
comment A Box for the integral or partial derivative d
One problem with these constructs is that they contain merely formatting and cannot be re-used as input if you copy them from the output cell. I thought you may be looking more for something along the lines of this, where I made sure the interpretation of the formatted output is preserved. But I guess you're happy with the solution you found... there isn't anything really simpler I can think of.
Apr
17
comment Recover data points from RGBColor of known ColorScheme
Related: How to change ColorFunction after plotting - also Jens, but a different person...
Apr
16
comment iterative programming
@user13674That's exactly how I'd do it (had I remembered to reply earlier...)
Apr
16
awarded  Enlightened
Apr
16
awarded  Nice Answer
Apr
15
comment Automatically highlight certain cells
Definitely use Grid, it's the more modern version for formatting tables. And it's backward compatible in the sense that the output of Grid in a text terminal is still formatted the same way as TableForm. The converse is also true: TableForm output in a notebook is internally formatted using GridBox.