I'm trying to do something like in the picture,     Which is a grid made of hexagons, like a 'hive'.  I  could generate a texture in another software like PS to add it, but what i want is to extrude upwards the yellow part, so the black parts are in depth.  How can i do this, using the options of Blender, without having to model it completely? i was thinking on making one hexagon and then duplicate it infinitely, but i think there should be another way for this.  Thanks in regards.
How would I be able to create a grill of sorts found on the front of some computer cases such as this one
What is the most elegant proof of the Pythagorean theorem? The  is one of the most popular to prove by mathematicians, and there are  (including one from ).    What's the most elegant proof?  My favorite is this graphical one:    According to cut-the-knot:     Loomis (pp. 49-50) mentions that the   proof "was devised by Maurice Laisnez,   a high school boy, in the   Junior-Senior High School of South   Bend, Ind., and sent to me, May 16,   1939, by his class teacher, Wilson   Thornton."      The proof has been published by Rufus   Isaac in Mathematics Magazine, Vol. 48   (1975), p. 198. Website is under maintenance - how to restrict access? Deleting files from Remote FTP-Server older than x days i've got a remote FTP server where i store some backups via cronjob.  The Problem is that i only got a little amount of space so im doing incremental backups. I want to keep the backups about 14 days.  I don't have any other access to the server except FTP and i don't now how to delete files older than x days. Every file got a name with a date in it  yxzNamezxy-date-y-m-d.tar.bz2 (datev-20100111.tar.bz2(   Hope to get some help here.  Cheers and thanks for the hopefully coming answeres,  Dennis  /Edit  I'm trying to use the curl thing which is mantioned in an answere with this part of code  curl ftp://$FTP_SERVER --user $FTP_USER:$FTP_PASS --list-only &gt; files.tmp declare -a aFiles let iCount=0 exec &lt; files.tmp while read sLine do         aFiles[$iCount]=$sLine         ((iCount++)) done  echo -e "\n Files: \n\n\n" echo ${aFiles[@]}  echo -e "\nfor ...\n\n\n" for sFile in $aFiles do         echo -e "\nFile:" $sFile done   but the secound loop doesn't give me more than 1 filename  Cheers,  Dennis How do I sudo a command in a script without being asked for a password? Proof by induction of summation inequality: $1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\dots+\frac1{2^n}\ge 1+\frac{n}2$ Find all polynomials $P(x)$ such that $P(x^2)=P(x)^2$ Find all polynomials $P:\mathbb{C}\rightarrow\mathbb{C}$ such that $$P(x^2)=P(x)^2 .$$   Here is what I tried:  First, it is easy to see the constant solutions, namely $P\equiv 0,P\equiv 1$.  Let $r$ be a root of $P$ (i.e. $P(r)=0$). It follows that all terms in the infinite sequence $r,r^2,r^4,\dots,r^{2n},\dots$ are roots of $P$. To avoid a polynomial with infinite roots, we have to have the sequence be periodic. So it turns out that either $r=0$, or the roots of $P$ are roots of unity of degree $2n$ for some $n\in\mathbb{N}$.  In the first case, we get $P(x)=xQ(x)$. Plugging in, we get $$x^2Q(x^2)=x^2Q(x)^2\implies Q(x^2)=Q(x)^2 ,$$ i.e. that $Q$ satisfies the same condition as $P$.  In the second case, we have $P(x)=(x^{2n}-1)Q(x)$. Plugging in, we get $(x^{2n}-1)Q(x^2)=(x^{2n}-2x^n+1)Q(x)^2$. I was not sure how to proceed from here. I have two exchange accounts on my iPhone 4. One that connects to my gmail, the other connects to my work's Lotus Notes. There are no overlapping contacts in the two accounts. There are also no contacts saved locally on my phone.   When I enable contacts in both accounts, I get two identical entries for each of the contacts in my gmail. If I disable the Notes exchange account, then there are no more duplicates. If I have Notes contacts enabled, and gmail contacts disabled then I have no contacts at all.  Does anyone know what is going on? Is this a problem with having multiple exchange accounts or is it a Lotus Traveler problem? (I tend to blame Notes for all the trouble in the world, but that is just my bias)  Thanks all. Question about Coulomb's law I am just very confsed about how to do these sort of questions where they give you a point in the middle of two charges. The farthest I've gotten in questions relating to coulomb's law, is using the formula \$F = {kq_1q_2 \over d^2}\$ to work out one of the unknowns when given two variables. Can someone please explain how you would do a question like this:  Two point charges of charge -2 µC and -3 µC respectively are separated by a distance of 15 cm. Point X is positioned at an equal distance away from each of the charges.      a. Determine the net electric field at X.     b. Find the point of equilibrium between the charges. How can I uninstall software? Seeing there are various ways to install on Ubuntu. What are the various ways to uninstall items?  Which ways always work? How can I be sure something was uninstalled? This is a small exercise that I just can't seem to figure out. When I see it I'll probably go 'ahhh!', but so far I haven't made any progress.  I'd like to prove that any linear functional $\phi$ on $\ell^\infty$ that is positive, i.e. for any $(x_n) \in \ell^\infty$ such that $x_n \geq 0$ for all $n \in \mathbb{N}$ we have $\phi((x_n)) \geq 0$, is a bounded linear operator and has $\|\phi \| = \phi((1,1,...))$.  Nothing I have tried worked so far, so any hints would be appreciated, thanks! What’s the best way to reload / refresh an iframe? I saw this question: .  My situation is a little different though.   My target moves, and the shooter moves.  Also, the shooter's velocity is added to the bullets' velocities, i.e. bullets fired while sliding to the right will have a greater velocity toward the right.   What I'm trying to do is to get the enemy to be able to determine where they need to shoot in order to hit the player.  Using the linked SO solution, unless the player and enemy are stationary, the velocity difference will cause a miss.  How can I prevent that?      Here is the solution presented from the stack overflow answer.  It boils down to solving a quadratic equation of the form:  a * sqr(x) + b * x + c == 0   Note that by sqr I mean square, as opposed to square root. Use the following values:  a := sqr(target.velocityX) + sqr(target.velocityY) - sqr(projectile_speed) b := 2 * (target.velocityX * (target.startX - cannon.X)       + target.velocityY * (target.startY - cannon.Y)) c := sqr(target.startX - cannon.X) + sqr(target.startY - cannon.Y)   Now we can look at the discriminant to determine if we have a possible solution.  disc := sqr(b) - 4 * a * c   If the discriminant is less than 0, forget about hitting your target -- your projectile can never get there in time. Otherwise, look at two candidate solutions:  t1 := (-b + sqrt(disc)) / (2 * a) t2 := (-b - sqrt(disc)) / (2 * a)   Note that if disc == 0 then t1 and t2 are equal. Is the Doctor Who episode 'Blink' the first use of the phrase "timey-wimey"? Font characters displayed as squares in Ubuntu 18.04 where do I use Database. Methods? There are several things that I don't understand. I know that zero is a real number, but I'm confused on the how and why aspects. What defines a real number, compared to a number that's considered non-real? For what reason is zero real, and how is it that a value such as infinity isn't when zero is?  Also, what purpose does zero even have? It's obvious that it's used as a place holder, but what value does it have alone? What makes it any different from other numbers? I realize that it is typically interchanged with nothing, but that would technically mean that zero is nothing—and that's not true. People have told me already so many times that zero does not necessarily mean nothing, and I figured it out a long while ago anyway. So, what I want to know is the actual value that can be associated with zero.  However, my question brings up another topic that has been argued and disputed about and disagreed on for years. Zero divided by zero, or 0/0. There are a lot of varying answers about this, but what's been constant throughout everything is that people claim 0/0 is not a real number. So, if I may ask, why is it that zero is considered a real number, and not 0/0? And why is it considered non-real in the first place? True, there is no defined value, but the expression is anything but meaningless; if it was, then there wouldn't be so many people trying to understand it. I guess what I'm trying to figure out is the reason behind the expression's classification as non-real—especially when the sole number of zero is real, despite not having an evident value.  This covers a few different things, so I was uncertain about what to make the title of these questions. I apologize for that. If anyone can answer, though, I'd be extremely grateful! Let $V,W$ be nonzero normed spaces over $\mathbb{K}$ such that $V$ is finite-dimensional.  Let $E$ open in $\mathbb{K}$ and $p\in E$.  Let $f:E\rightarrow W$ be Gâteaux-differentiable at $p$.  Is $f$ necessarily Fréchet-differentiable at $p$ in this case?  I think this is not true in general, but cannot find a counterexample. What would be a counterexample? Unity-like Dashboard for Gnome fallback? Is there any way I can run the Unity dashboard (or something similar, like Bolt for Gnome 3) in Gnome Fallback? in -> inner  out -> outer / (outter?)  What is the history or set of rules behind why 'inner' doubles the 'n' but 'outer' doesn't double the 't'? Textbook recommendation for computational physics