n = 4 metric_len = 2 * n+1 matrix = [[0] * metric_len] * metric_len print(&quot;during creating&quot;) for i in range(0, metric_len):     for j in range(0, metric_len):         if i &lt; n and j &lt;= n:             matrix[i][j] = max(n - i, n - j)         elif i &lt; n and j &gt;= n:             matrix[i][j] = max(n - i, j - n)         elif i &gt;= n and j &lt;= n:             matrix[i][j] = max(i - n, n - j)         elif i &gt; n and j &gt; n:                        matrix[i][j] = matrix[j-n][i - n]     print(matrix[i]) print('\n') print('After creation') for item in matrix:     print(item)  result during creating [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 3, 3, 3, 3, 3, 3, 3, 4] [4, 3, 2, 2, 2, 2, 2, 3, 4] [4, 3, 2, 1, 1, 1, 2, 3, 4] [4, 3, 2, 1, 0, 1, 2, 3, 4] [4, 3, 2, 1, 1, 3, 3, 3, 3] [4, 3, 2, 2, 2, 2, 2, 2, 2] [4, 3, 3, 3, 3, 3, 3, 3, 3] [4, 4, 4, 4, 4, 4, 4, 4, 4] After creation [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4] [4, 4, 4, 4, 4, 4, 4, 4, 4]  When I was printing the whole matrix in i's for loop, just after print(matrix[i]) so all rows of matrix are equivalent to that row((matrix[i]). Why the whole matrix gets updated?
I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?
Can I reposition AdSense ads with Javascript (for responsive purposes)? I have a responsive blog where ads are displayed in the sidebar. On mobile devices however, the sidebar is pushed to the bottom below the posts.   So what I'd like to do is move the ads from the sidebar and insert them into the post itself on mobile devices   I do this using javascript:  &lt;div id="main"&gt;     &lt;div id="article"&gt;         &lt;div class="post"&gt;             &lt;p class="intro"&gt;&lt;/p&gt;             &lt;p class="text"&gt;&lt;/p&gt;         &lt;/div&gt;     &lt;/div&gt;     &lt;div id="sidebar"&gt;         &lt;div class="adbox-1"&gt;&lt;/div&gt;     &lt;/div&gt;     &lt;/div&gt;  &lt;script&gt;     jQuery(document).ready(function(){          // AD REPOSITION         if ($(window).width() &lt; 769) {             $('.ad-box1').insertAfter($('.intro'));                    }      }); &lt;/script&gt;   The ads are always loaded in the sidebar, but if the screen width is below 768px, they will be moved somewhere else.  I wonder if this would violate AdSense terms of service? A star's collapse can be halted by the  due to the Pauli exclusion principle. In extreme relativistic conditions, a star will continue to collapse regardless of the degeneracy pressure to form a black hole. Does this violate the Pauli exclusion principle? If so, are theorists ok with that? And if it doesn't violate the Pauli exclusion principle, why not? Badges with long names overflow on the profile page How do I add "citations" at the end of the document as done here? Are employments in universities affiliated (or named) with a specific religion restricted to people with the same religion? I just saw an ad in mathjobs.org about an opening in a Catholic university, see . I am not christian. So I was wondering to be eligible for employment in a university or college affiliated with a specific religion, should the applicant  have the same religion, or other people from other religions (or even non-religious people) are eligible to apply as well? Basis of cotangent space What is the design pattern for processing command line arguments Which preposition in front of "line" — "on", "in", "at"? Is the energy density of vacuum uniform in the whole universe? This might be subjective, I don't know. However, it's a serious problem for me. My electrical bill is outrageous. It's three times as large as my next-door neighbor, and four or five times the size of my neighbor's across the street. It's worse in the summer (I live in central TX), but I've had the air conditioner inspected, and while the house is right at the maximum capacity for our unit, the unit should still be able to take care of the load. That also doesn't explain why our winter bills are larger than the comparables.  What I would like to do is check the amount of current drawn by each running appliance and calculate where all my money is going. I just don't know how to go about doing this. Error: Can't open display: 0 I installed WSL2 and I want to access WSL2 GUI apps from Windows 10. For this, I installed Xming and start it in "No client" mode. Xming startes, ok. After I open the WSL2 terminal and there execute these commands  export DISPLAY=:0   And after  xeyes   And get error   Error: Can't open display: :0   X11Forwarding checked, yes. To my knowledge there are three types of acceleration when a body (e.g. a rod) is moving in a circle about an axis. These are:   Angular acceleration : this is the rate of change of angular velocity. Tangential acceleration : this is the linear acceleration of the system in a tangential direction to the circle and equals the radius times the angular acceleration. Radial/centripetal acceleration : this is the linear acceleration of the system that is directed inwards towards the center of the circle.   I also think there are two types of velocity:   Linear velocity: this is its velocity in the tangential direction and is constantly changing Angular velocity or angular frequency: this is the rate of change of angle.   Is the above correct? And have I missed anything? The replier's From email address is modified when Marketing Cloud RMM forwards an email to the routing address We've set up RMM to forward replies to routing address and SFMC adds our subdomain to the replier's From email address (i.e. replier@gmail.com becomes replier.gmail.com@oursubdomain.com). However, their reply-to address remains the same.  It seems like DMARC Forward Reply Rewrite is enabled, but we were advised not to touch it as that may affect email deliverability.  Is there any workaround to this? And what will happen if we disable this feature? Where can I find information about upcoming special issues in a field of study? How can I find information about upcoming special issues related to a special field of study? There are good websites for upcoming conferences but I could not find any place to search for special issues. Problem Currently, I am playing on a server where hoppers transport items at the rate of 64 items a second, and this has proved very difficult to build a sorter for. I'm not at all proficient in Redstone building but have tried building basic sorters and ones that I have found on YouTube and I haven't gotten anything to work. Solution Hopefully one of you is really good at Redstone and can help me design a sorter that can work under these conditions. (I need the sorter that can sort items while I AFK kill witches with a looting 47 sword P.S. most of the problem is with the sorter itself because no items will stay in the sorter hopper (bc the whole stack goes into the chest so the hopper doesn't have anything to go off of to sort) so any solution to that would be helpful as well. We want to show that if $a,b\in G$ where $G$ is a finite Abelian group, we have  $\operatorname{LCM}(|a|,|b|) = |ab|$ given that $ab \neq e$.   How I approached this question was by saying let $\operatorname{LCM}(|a|,|b|) = L$. Then if we show that $L$ divides $|ab|$ and $|ab|$ divides $L$ then $|ab| = L$. Showing that $|ab|$ divides $L$ was fine. But then I am having trouble with the second part that is showing $L$ divides $|ab|$. For this, so far I have:  Consider $(ab)^{|ab|} = e = a^{|ab|}b^{|ab|} $  since we know $a \neq b^{-1}$ by assumption then we can conclude that $|a|$ divides $|ab|$ and $|b|$ divides $|ab|$. We know that $L = \frac{|a||b|}{\operatorname{gcd}(|a|,|b|)}$ from here can we conclude that $L$ divides $|ab|$? Handling Calls to Remove a Moderator This discussion informed our process for seven years, but eventually required updates and augmentation. For discussion regarding the successors to this process, please see:    Stack Exchange has some of the best Moderators around — seriously — and that is due in no small part to the communities who scrutinize and vote in our Moderator elections.  We have a rather formal process for electing moderators, but up until now  has been quite informal. On those rare, rare occasion when things just aren't working out, you can see why it becomes such a sticky business to remove someone from a democratically elected position. Our current process is one of &quot;we've got your back.&quot; The Community Team routinely monitors moderator activities, so if a moderator violates the  or fails to uphold the , we can and do intervene. If the disputes and problems persist without resolution, eventually we can ask someone to step down. That's not good enough. We need a much more transparent and prescribed process for when — and more importantly how — to intervene when on-going problems are going unresolved. In urgent situations, we'll step in to protect a site, but ideally the process should be impartial and not subject to accusations of Stack Exchange simply applying undue influence over a community when the whim strikes. The Question: Before we start bouncing around ideas internally, I'd like to hear what you think. What process should be in place to add some checks and balances to deal with higher issues like possible impeachment of a moderator? When and how would such a process come into play? How should such situations be resolved? How do we keep it from being abused? Have at it. This is a round table vetting of ideas. Why did Dumbledore make it less difficult to get to the Sorcerer's Stone? The Sorcerer's/Philosopher's Stone was removed from Gringotts to be placed under the most impenetrable of protections at Hogwarts under Dumbledore's custody. But it seems clear Dumbledore took protections which could have been impenetrable, and deliberately made them less so, such that at best they would only slightly slow down anybody trying to access the Stone, rather than just plain block them.  For example, after the Devil's Snare, you have a locked door enchanted such that it cannot be opened by any charm or other means except its own assigned key. That's a great protection, potentially an impassable barrier if the key is not available.  But the key is then left right there in front of the door in the same room.  At least the key is flying around the ceiling. But there are broomsticks right there in the same room, too.  The room with the fires front and back—that could also have been a solid defense—deadly fires that cannot be passed through unless you drink very specific potions tailored to each particular fire's properties.  Except that those potions providing safety are put right there in the same room.  At least, perhaps, they're surrounded by other bottles, some of which contain poison. With no way to know which bottle is safe, that could still almost be a solid protection.  Except that a piece of paper with a logic puzzle detailing exactly which bottles are which is put on the table with them.  Dumbledore always had reasons, and those reasons were always virtuous. What was he up to, deliberately weakening the protections in this way? How do I write a correct micro-benchmark in Java? "Email" or "e-mail"? Which way of writing the word: "Email" or "e-mail" is correct? Both variants seem to be in wide use. If both ones are okay, maybe there is a difference in contexts they have been used (one is more formal than the other)?