### 2 Formal Languages: Trouble understanding powers

Lee Brindley today at 00:18. 1 answers, 0 views formal-languages
I've run into an argument with some peers about how to perform power operations on languages. Say: A = {2,00} At first myself and my peers were all in agreement that say for instance A^3 would output: A = AAA...

slm 07/22/2018 at 20:29. 1 answers, 10 views linux centos grub2 vagrant
I recently downloaded the official centos/7 Vagrant Cloud VM. While trying to access its GRUB2 menu during a reboot via the e key, I ran into a prompt for a username + password. I was unsuccessful in finding this referred...

### 2 How to draw $y^4 - y^2 = x$?

Charles 07/22/2018 at 20:25. 2 answers, 37 views tikz-pgf pgfplots tikz-styles
I am having some trouble to draw the equation $y^4 - y^2 = x$. Can someone help me? Thanks a lot!

### 5 Cantor set with pairs of points identified

Forever Mozart 07/22/2018 at 20:14. 1 answers, 24 views general-topology cantor-set
Consider the middle-thirds Cantor set in $[0,1]$. I want to identify points in the following way. First, identify the two points $1/3$ and $2/3$. Then, idenfity $1/9$ with $2/9$, and also identify $7/9$ with $8/9$. At the third step there...

### 1 Echoing the pts number of the terminal you are running on?

Garmekain 07/22/2018 at 19:14. 1 answers, 17 views text-processing grep

### 1 question about determinant variety in Karen Smith's “An Invitation to Algebraic Geometry”

Newbie 07/22/2018 at 16:20. 2 answers, 31 views linear-algebra algebraic-geometry
I don't understand in the example below: If $k \geq n$, then the determinant variety is the whole space ?

### 3 Odd custom theorem behavior when trying to set default value of optional argument

Jessica 07/22/2018 at 16:01. 1 answers, 25 views macros environments theorems amsthm optional-arguments
MWE: \documentclass{book} \usepackage{amsthm} \usepackage{enumitem} \usepackage{xparse} \usepackage{hyperref} \usepackage{lipsum} \newtheoremstyle{fctaylor}% name {\topsep}% Space above {\topsep}% Space below {\normalfont}% Body font {}% Indent amount (empty = no indent, \parindent = para indent) {\bfseries}% Thm head font {}% Punctuation after thm head {0pt}% Space...

### 1 How to get modem mode using sed or awk from a modem output?

Pilot6 07/22/2018 at 15:29. 3 answers, 15 views command-line bash
I am not an expert in bash and I have troubles in filtering out the correct substring. I have echo "AT^SYSCFGEX=\\\"0201\\\",3fffffff,2,4,7fffffffffffffff,," that results as AT^SYSCFGEX=\"0201\",3fffffff,2,4,7fffffffffffffff,, How can I get 0201 as the result? I am struggling with that....

### 3 Does factorisation always exist?

Xavier Yang 07/22/2018 at 15:22. 1 answers, 44 views abstract-algebra ring-theory
In the definition of UFD, there are two parts: existence and uniqueness. It is well-understood that the uniqueness property is useful e.g. $\mathbb{Z}[\sqrt{-5}]$. But isn't it true that every integral domain must satisfy the existence property? Existence: Each element in...

### 1 How to choose the random seed?

BrunoGL 07/22/2018 at 15:08. 2 answers, 15 views hyperparameter hyperparameter-tuning randomized-algorithms
I understand this question can be strang, but how do I pick the final random_seed for my classifier? Below is an example code. It uses the SGDClassifier from SKlearn on the iris dataset, and GridSearchCV to find the best random_state:...

### 3 How to draw line with different markers by pgfplots or tikz?

larvacy 07/22/2018 at 15:06. 1 answers, 28 views tikz-pgf pgfplots line
I would like to draw a line that is similar to the one shown. Now I do something like this. Can someone help me ? Thank you! \documentclass[border=3pt]{standalone} \usepackage{tikz} \usepackage{pgfplots} \begin{document} \begin{tikzpicture}[scale=0.95] \begin{axis}[ width=9.5cm, height=5.5cm, ymin=0.0,ymax=1.0, ytick={0,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1.0}, ymajorgrids=true, grid style=dashed,...

### 3 Twisted Cylinder

quiliup 07/22/2018 at 14:12. 1 answers, 19 views mesh transforms topology geometry
I want to create a mesh like this: with a vertex on every edge-crossing so that every face is kite (nearly rhombus) shaped. The above image was created just by rotating the top of two cylinders in different directions and...

### 1 What is the cost of a +1 Mithral Heavy Steel Shield?

FrancisJohn 07/22/2018 at 14:03. 1 answers, 21 views pathfinder magic-items equipment special-materials
I need a breakdown of the item costs: Base price Mithral +1 Enchantment I’ve read that there have been conflicting prices between the Core Rulebook and Ultimate Equipment.

### 1 Are followers of other Abrahamic faiths considered Noachide?

Reggie O'Donoghue 07/22/2018 at 13:44. 1 answers, 30 views gentiles christianity noachide-laws islam
Are Christians, Muslims, Samaritans, Bahais, etc considered Noachide, and do they have a part in the world to come? What about Karaite and Falasha Jews?

### 2 Found a lot of SSH login attempts in auth.log

terresquall 07/22/2018 at 13:30. 1 answers, 105 views ssh security sshd
I'm running my own DigitalOcean Droplet on Ubuntu. Today, I found that my SFTP connection to said Droplet was a little laggy when doing work on it, so I checked /var/log/auth.log files to see what was happening. I saw that...

### How many cubic feet can 1 peltier cool efficiently?

Lena Bru 07/22/2018 at 13:29. 3 answers, 46 views peltier cooling
I want to build a mini fridge, however, I want to build it a bigger than the ones showed in the tutorials I've watched. For that I assume I need more than one peltier to cool it. However, for that...

### 4 Grandpa can't even tell time? Another Grandpa Mystery

DEEM 07/22/2018 at 13:13. 2 answers, 38 views riddle knowledge
Grandpa was waiting impatiently in the Waiting area of Yale Hospital in Connecticut US. It was past midnight. His second daughter was giving birth to her first child (C-section). His son-in-law came out of OR and told him happily that...

### 1 Would a “perfect” clone ever rebel against the original?

Magus 07/22/2018 at 13:09. 5 answers, 58 views science-fiction psychology
I'm creating this character that has the ability to replicate herself. Her power works like this: She can make a perfect copy of herself, which means that even her memories, thoughts and feelings are exactly the same in the exact...

### 1 How to find files with a specific pattern in the parent and child directory?

Ashwin B 07/22/2018 at 12:50. 1 answers, 24 views linux files grep find cygwin
How to find files with a specific pattern in the parent and child directory of my present working directory using a single command ? Filename - test.txt, the file has the pattern nslookup This file is present in 3 directories...

### 6 Charged particles

Sal.Cognato 07/22/2018 at 12:29. 1 answers, 36 views probability
We are creating a circular hub consisting of charged 0 and 1 particles next to each other, beginning with four of them: 0, 1, -0 and -1 in this order. Every 1 sec we randomly select one of each...

### 2 When can I kill my character?

When is it acceptable to kill a character? (and if possible, when is it most appropriate?) BTW, I'm not talking just about a protagonist; I'm talking about any of my characters, whether they're MCs or extras is irrelevant.

### 1 Help with tikzcd

Emma 07/22/2018 at 12:21. 2 answers, 21 views tikz-pgf displaystyle
So Im having a little problem with a tikzcd-figure in my Thesis. It looks very 'squeezed' - if you understand. Can anyone help? I can simply not get it to look right \[ \begin{tikzcd}[row sep=huge, column sep=small] & Finanspolitisk\,disciplin \arrow[dash]{dr}{[Den\,liberale\,model]}...

### 1 How can I make my anti-heroic protagonist more likable?

A while ago, I asked if there any possible way for my series to avoid causing Darkness Induced Audience Apathy. A well thought-out response stated that unless I give my readers a reason to care about my protagonist (due to...

### Line integral over curve defined piecewise

CAF 07/22/2018 at 11:56. 1 answers, 0 views multivariable-calculus