Slicing list of list in python, jumping one item
Understanding slice notation
PostgreSQL crash when connection failed Error log is:  016-02-21 21:22:34 GET DETAIL:  Connection matched pg_hba.conf line 83: "host    all             all             ::1/128                 md5" .... .... 2016-02-21 21:22:37 GET DETAIL:  Connection matched pg_hba.conf line 83: "host    all             all             ::1/128                 md5" 2016-02-21 21:22:37 GET FATAL:  password authentication failed for user "postgres" 2016-02-21 21:22:37 GET DETAIL:  Connection matched pg_hba.conf line 83: "host    all             all             ::1/128                 md5" 2016-02-21 21:22:37 GET LOG:  CreateProcess call failed: A blocking operation was interrupted by a call to WSACancelBlockingCall.       (error code 299) 2016-02-21 21:22:37 GET LOG:  could not fork new process for connection: No error 2016-02-21 21:22:37 GET LOG:  incomplete startup packet 2016-02-21 21:22:38 GET FATAL:  password authentication failed for user "postgres" 2016-02-21 21:22:38 GET DETAIL:  Connection matched pg_hba.conf line 83: "host    all             all             ::1/128                 md5" 2016-02-21 21:22:42 GET FATAL:  password authentication failed for user "postgres" 2016-02-21 21:22:42 GET DETAIL:  Connection matched pg_hba.conf line 83: "host    all             all             ::1/128                 md5" 2016-02-21 21:24:26 GET LOG:  could not receive data from client: An operation on a socket could not be performed because the system lacked sufficient buffer space or because a queue was full. 2016-02-21 21:24:26 GET LOG:  incomplete startup packet 2016-02-21 21:24:29 GET FATAL:  password authentication failed for user "postgres" 2016-02-21 21:24:45 GET PANIC:  could not write to log file 000000010000000100000041 at offset 4259840, length 8192: Invalid argument 2016-02-21 21:24:45 GET STATEMENT:  COMMIT 2016-02-21 21:24:53 GET LOG:  server process (PID 470944) was terminated by exception 0xC0000409 2016-02-21 21:24:53 GET DETAIL:  Failed process was running: COMMIT 2016-02-21 21:24:53 GET HINT:  See C include file "ntstatus.h" for a description of the hexadecimal value. 2016-02-21 21:24:53 GET LOG:  terminating any other active server processes   Can anyone help to solve the problem? I spent many hours but didn't find a solution.   Postgres version 9.4 Operating System: Windows  postgresql.conf is:  listen_addresses = '*' port = 5432  max_connections = 100 shared_buffers = 128MB   dynamic_shared_memory_type = windows   pg_hba.conf is:  # IPv4 local connections: host    all             all             127.0.0.1/32            md5 host    all             all             0.0.0.0/0               md5 How to answer a negative question without ambiguity? I faced a problem to answer a negative question, for example, when someone asks you:      Don't you have any money?   It's a yes/no question but how should one answer the question without ambiguity?  When you answer "yes", does it mean "yes, I don't have any money"? or the other way "Yes, I do have money"? the questioner may think you are agreeing to the negative, that yes, you do not have any money.  I know it's better to answer with "on the contrary" but is it possible to answer yes or no? I see a lot of example code for C# classes that does this:  public class Point {     public int x { get; set; }     public int y { get; set; } }   Or, in older code, the same with an explicit private backing value and without the new auto-implemented properties:  public class Point {     private int _x;     private int _y;      public int x {         get { return _x; }         set { _x = value; }     }      public int y {         get { return _y; }         set { _y = value; }     } }   My question is why. Is there any functional difference between doing the above and just making these members public fields, like below?  public class Point {     public int x;     public int y; }   To be clear, I understand the value of getters and setters when you need to do some translation of the underlying data. But in cases where you're just passing the values through, it seems needlessly verbose. Example of a finite non-commutative ring without a unity Give an example of a finite, non-commutative ring, which does not have a unity.    I can't think of any thing which fits this question. I was thinking $M_2(\mathbb{R})$ but it has the identity. Any help is appreciated. Let us say I have added a PPA that has X package that I want but it also has Y package that I do not want to use or receive updates from. How can I, from the same PPA, receive updates for a specific package but deny updates from the same PPA for other packages.  A step by step example would be good since this has happened to me in several PPAs that have a particular package I want but also add a whole bunch of others that I do not yet want to update. Resolving heteroscedasticity in Poisson GLMM How can I convert monsters from D&D 3 or 3.5 to 2ed monsters? "modified" link in the home page questions list does not contain "?lastactivity" parameter I have just noticed that the "modified" link for  does not contain "?lastactivity" parameter in homepage questions list:        When , it's changing to https://meta.stackexchange.com/questions/253359/list-of-communities-with-base-css-updates-completed/286876#286876 as it should, and showing the deleted answer to those who can see it.  Other questions I checked are not affected. Possible way to reproduce might be question with zero answers, where the "modified" was caused by a now-deleted answer. In Unity, are there any pre-defined shortcuts, e.g. to open the dash or unhide the launcher? How do I get the current date and time in PHP? Which PHP function can return the current date/time? I'm trying to use Python to place a camera. I know the camera's location, and the forward and up vectors for the camera (i.e. the direction it's pointing and its orientation). How do I do this?  I know that it's possible to calculate a raw world matrix from the above information, which I can then apply to the camera, but I was rather hoping not to have to. Is there an easier way? OpenGL Line Width Lie Algebra of U(N) and SO(N) Cancelled cut and paste, what happens? How can I crack a 16 bit hash/CRC/checksum with a large sample set? AmpScript to select Right or Left characters from a string Is there an AmpScript function that can be used in an equivalent manner to sql left, right and mid functions?   Thanks, Mark Add a downvote option in the VLQ review There are many answers that are well-formed and well-formatted but are simply plain wrong or misleading. When reviewing, I often have a hard time deciding which action to take, as:   Looks Good: is OK per se but I would never say "good" (would work if the wording was changed slightly), Edit: The question is formatted well and editing it to be right would go against the intent of the author, Recommend deletion: this looks like the most reasonable choice, but I wouldn't flag it if I were browsing the site in normal mode, Not sure: I am quite sure what is wrong but I end up clicking this because the other three options do not seem fitting.   My proposal is to add a fifth option - Downvote that would make it easier to choose in case of such answers. How to flag a typo question I came across  today. In reading the answer and the comments it turns out that the issue was just a simple typo that the OP made. So that being the case I decided that this question probably needs to be closed since this will not be helpful to any future vistors. However, in looking at the flag reasons (I don't have the close ability yet), I don't see a flag that would be appropriate.   I know some of these options might still be influx because of the . However, until a different off-topic flag description is created, how should this be flagged? Or should this not be flagged at all and just allowed to live on or wait for a user with close votes to use a custom off-topic close option? Poking around the people's profiles to see how the  I keep seeing things like this:  It looks strange to have a 25/5 progress on a badge, but the dialog explains that what this user is missing is a positive record of asking. The  is: (total questions - negative questions - closed - deleted)/total questions &gt;= 0.5  If you look at , it's hard to see how his asking record could be anything but exceptional. According to  his asking record is 0.875. The problem is that he asked many of his questions in the early days of the site that were well-received, but later deleted. Some were deleted after the question was . My suggestion is that we change the asking record formula: (total questions - negative questions - closed - early deleted)/total questions &gt;= 0.5  The early deleted variable counts only questions deleted within 60 days of being asked. I picked 60 days because it's the dividing line between being able to . After looking through the list of people who would get the Curious badge on Stack Overflow with this change, I noticed a few things:  Many of them have self-deleted questions on their record. Often these are questions that were asked and basically ignored. After a few months, the original asker went back and deleted their question. It's hard to know what happened in each individual case, but my guess is that they never found a solution to their specific question and worked around the issue instead. (I have a few of those, but I'm not courteous enough to delete them.)  These users don't tend to ask the same question over and over again. I ran a similar test that excluded self-deleted questions. That group included a lot of cases of people asking a question, not getting an answer after a day or two, deleting the question, and asking the same question again. This strategy doesn't work if you wait two months to delete your first question.  Two mods (George Stocker and Gordon), Tim Post, and myself are on the list of users who would get a Curious badge under this system. On Meta Stack Exchange 5 current employees would be newly eligible for the badge. In my (admittedly biased) opinion, these are curious users.  I did some spot check on the lower end of the reputation scale. Every user I looked at fit my model of the ideal recipient of the Curious badge; they asked mostly upvoted questions with few closed questions. This change would add about 3286 new Curious badges on Stack Overflow, so there will certainly be a few exceptions I didn't find. But I think they are more than balanced by the clearly deserving users who will be awarded new badges.    Proposal: For the Curious, Inquisitive, and Socratic badges, don't count questions deleted 60 or more days after asking as deleted for the purposes of calculating asking record. These questions may still count as negatively scored or closed, if applicable. Days that include deleted questions, no matter when they are deleted, do not count toward the days asked criteria.   Modified Proposal: For the Curious, Inquisitive, and Socratic badges, don't count questions deleted or closed 60 or more days after asking as deleted or closed for the purposes of calculating asking record. These questions may still count as negatively scored, if applicable. Days that include deleted or closed questions, no matter when they are deleted or closed, do not count toward the days asked criteria. On Stack Overflow, that would add about 665 Curious badges, including two more for moderators (casperOne and 0x7fffffff) and one for an employee (Oded). On the opposite end of the reputation scale my spot checks are a bit muddier. Instead of a small number of deleted (and usually closed) questions, this list turns up users whose latest questions still aren't all that interesting. Even so, on balance a few extraneous bronze badges seem worthwhile in exchange for acknowledging truly curious users. php/mysql with multiple queries