Converting a 2d surface into a 3d volume

I have a 2d surface shown in the image below using ListPlot3D[]:

image It is generated with one line of code:

ListPlot3D[RandomVariate[UniformDistribution[], {10,10}]]     

Currently, it’s a ‘white noise’ surface, meaning the surface is more or less random between zero and one. I’d like to give this thickness (so I can ultimately 3d print it).

I’d like the remaining 5 sides to be flat, so that I’d end up with a "cube" with one surface jagged.

Is there an easy way to do this? Essentially just fill in everything below the surface?


Can VeraCrypt encrypted volume be tampered with?

Reading on the security of Borg backups and both encryption and authentication is used (Encrypt-then-MAC).

My understanding is authentication is used to prevent tampering which is especially important for backups vulnerable to unauthorized access (cloud storage or safety deposit boxes for example).

Reading on the security of VeraCrypt (which uses XTS), I can’t find anything about authentication.

XTS mode is susceptible to data manipulation and tampering, and applications must employ measures to detect modifications of data if manipulation and tampering is a concern: "…since there are no authentication tags then any ciphertext (original or modified by attacker) will be decrypted as some plaintext and there is no built-in mechanism to detect alterations. The best that can be done is to ensure that any alteration of the ciphertext will completely randomize the plaintext, and rely on the application that uses this transform to include sufficient redundancy in its plaintext to detect and discard such random plaintexts."

Can VeraCrypt encrypted volume be tampered with?

Security loopholes while mapping .kube/config file on to docker as volume

I have a scenario where I have to install Kubernetes on a public cloud and access the Kubernetes via kubectl from a VM on my laptop.

Kubectl accesses .kube/config to connect K8S API-Server to do the required operation.

There is an application that is running as docker inside the VM and connects to K8S using .kube/config that is mapped as volume. That is -v $ HOME/.kube:/home/test/.kube

Is there any security loopholes should I be aware of?

Determining Volume of an Irregularly Shaped Triangular Prism

I need help using Mathematica to determine the volume of an irregularly shaped triangular prism. I have very little experience with Mathematica but thought this task could easily be performed using the program.

The shape generated should look like:


Prism[{{3.767, 4.523, 1}, {0, 0, 0}, {7.948, -2.451, 0}, {3.699,

8.156, 1}, {1.146, 10.24, 0}, {4.837, 10.24, 0}}]]

I’ve tried using the Volume[] function but with no luck. Any help would be greatly appreciated!

Setting up secure personal system for managing sensitive data and high volume trading

So I’ve been mining and investing bitcoin for almost 5 years, and have reached the point where the volume of cryptocurrency I manage demands I take the time to create a secure cloud environment and set up a secure laptop. The fact that I handle some assets for family and close friends makes this need ever more pressing.

More generally, I am looking to establish a more secure digital presence, and believe an environment I can trust is the place to start. I should be able to trust this set up for any application (within reason, I’m not smuggling state secrets).

I have a beginner’s understanding of security principles, and experience in software. I am comfortable with less user friendly UIs and know my way around a terminal. I’m willing to put 10-20 hours into setting this up, and am ready to familiarize myself with material if necessary. This is what I’m looking for:

  1. Remote system with solid hard drive encryption. Nothing crazy, I’m thinking 256 bits, generating a random sequence of words that I will be able to memorize. I want to minimize the data that is left vulnerable when I connected, such that I don’t have to worry about theft after logging in.

  2. Encrypted traffic and browsing from cloud system, an anonymous VPN or Tor would be ideal.

  3. Backup mechanism. I need to be able to access the system from any trusted computer, in the event of damage to the laptop.
  4. Firewall settings on laptop that allow only traffic to and from cloud environment. Essentially a close to cold system with only one connection, SSL.
  5. Disabled/non-existent physical ports to protect from malicious software and USB killer type things. I am thinking a VM instance for the cloud side, but I have no experience in dealing with that stuff, so I need some guidance. On the physical end, I don’t really know where to start, and would very much appreciate any help.

I know this may sound like overkill, but rest assured I’m not a paranoid maniac, I just want to make sure security is not a concern.

Veracrypt encrypted file – how to expand the Volume and what are Drive Letters?

can you help me understand some questions about Veracrypt:

  1. If you have created an encrypted file but the volume which you selected for it needs expansion, is it from security standpoint fine to just use the available option “expand volume” to adjust the file’s volume? Or is it for some reason better to create a totally new encrypted file with your desired larger volume?

  2. What is the meaning of all the different Drive Letters (A-Z)? Do you have to mount a file from a specific drive letter, or can you mount from any letter?


Optimal distribution of N points in non euclidean volume, where each point is furthest away from the others

Given N points, I want to find the optimal configuration for which all the points are as far away from each other as possible.

The metric I’m considering is an approximation to the perceived distance between two colors:






The colors are constrained between 0 and 255. And there are N colors of maximum pair distance I want to find, in addition to these N colors, there’s a point in the origin (black) and in the topmost right-front corner (white) which are fixed in place.

This reminds me of sphere packing, but I don’t know the optimal size of the sphere so that they’d fill the whole volume… And since this metric is not translation invariant, I’m not sure how to calculate the sphere positions even if I knew the sphere size.

I’ve tried minimizing some cost functions, such as


or the columb force inspired


But it’s not very efficient, and is very dependent on initial guess (and it seems my euclidean grid-based guess isn’t optimal).

Is there a generalized form of the sphere packing algorithm which would give me the global minima, without the need to minimize these complex cost functions and fall into the many local minima, or get stuck in zero gradient areas?

Which FLUSH command before taking EBS volume snapshot?

The FLUSH TABLES WITH... command has a few flavors. The manual meagerly describes the differences between:


Am I interpreting the manual correctly that if one needs to perform a disk volume snapshot, such as the EBS Snapshot, the preferred way now is to use the FLUSH TABLES WITH READ LOCK AND DISABLE CHECKPOINT right before initiating the snapshot?

sudo update-grub:Sourcing file `/etc/default/grub’ Generating grub configuration file … error: invalid volume

I have re-Installed the Ubuntu after accidentally deleting the Ubuntu partition from windows without proper procedure & configuration of Ubuntu, so in result I couldn’t able to run Ubuntu and cant use the freed space. I have installed the Ubuntu in same partition which I was deleted improperly to overcome this problem, now I can use the Ubuntu but there are some issue.

I am using the dell Inspiron model so i avoid the issue of the kernel checking the graphics driver which causing the boot problem I had to change the some of grub file (Reference Video: After following the video in last I had to run the sudo update-grub which causing this error. Error after running command

And also there is number other files folder are created because of improper removal of my previous and re installation of Ubuntu again As you can see here

Or should I removed the all Ubuntu now with all configuration and Ubuntu now, will this work?

Any help would be appreciated.

Note: Previous and re-installed version are both Ubuntu is 18.04.3 LTS

Headphone volume is extremely low and noisy

I’m running Ubuntu 19 on my Samsung notbook7 2019 version(NT750XBV-G517A).

I installed windows 10 and ubuntu 19 on this laptop. but when I use a headphone, the sound from the headphone is extremely low (but I can recognize which music is playing) and there is a lot of noise. The thing is there is no problem on windows 10 at all.

I’ve tried reinstalling pavcontrol, alsa, alsamixer, sort of all the solution on the internet about ‘no sound’. but it didn’t work at all.

Here are a sound card and chip information from alsamixer
Card: HDA Intel PCH
Chip: Realtek ALC256

Please help! Thanks you in advance