Novadays it is very hard to study with an unstable computer.  I had my laptop for about 5 years and a year ago I installed Ubuntu alongside Windows (which I never used). I had no problems for about a year, but two weeks ago my computer boot to initramfs.   Simple solutions like "just type 'fsck /dev/sda1' " didn't work so first time I reinstall Ubuntu (and deleted Windows). But after a few days the problem came back. So, I learned, how to fix problem with live CD (based on ). But the problem appears again and again after about 3 days.   Today I couldn't boot Ubuntu.  So, my question is: "What can cause Ubuntu to boot in initramfs so often? How can I avoid surprises again?"
I am running an HP pavilion dv6000 dual boot win7 and Ubuntu 12.04. (well, up until today).  After a reboot, the boot process drops to the BusyBox shell and I end up at the prompt:  BusyBox v1.18.5 (Ubuntu 1:1.18.5-1ubuntu4) built-in shell (ash) Enter 'help' for a list of built-in commands.  (initramfs)   I've been researching others who have had this same problem, but haven't been able to find any of those solutions to work for me.  I tried the method described , and after the final command   mount -t ntfs-3g /dev/sda1 /root -o force   it does nothing and gives me another (initramfs) prompt.  I can boot to a live CD (USB) and get to a terminal, but it doesn't seem to do much good, as I can see the /dev/sda1 in the ls command, but it doesn't recognize it when I try to cd to it.  One more question: using the command fdisk -l how can I tell which mount point (sda1/sda2) is my windows partition and which one is Ubuntu?
How can I enable multiple users login at a time in remote system? Recently we bought dedicated server with Windows Server 2012 Standard.It's allowing 2 people at a time.So I want to allow more people at a time.  How can I do this? I have several files that I ftp each hour.  The receiving system needs to have some sort of identifier that they came from the same batch, so I would like to append a timestamp to the filename.  That alone is fairly easy, but since I want each file to have the same timestamp (so it can serve as the batch identifier), I cannot figure out how to do this.  So, I have:  file1.txt file2.txt file3.txt   And I want to have:  file1_20141110184303.txt file2_20141110184303.txt file3_20141110184303.txt   Any use of the date +%Y%m%d%H%M%S after the first use will obviously result in a different values in seconds, so I would like to have the first timestamp appended to the remaining files. We have a view for a type of node that includes a Private File.  We cannot see a way to add an exposed filter, such as "Contains any word", and have it filter based on the file's name.  Are we missing something obvious? So before I reformatted (to get rid of Windows), I simply used this command to open documents by putting it at the end of the ~/.bashrc file:  alias commandless= 'gnome-open ./Documents/the-linux-command-line.pdf; gnome-open ./Documents/linux.odt'   But now everytime I start the terminal, it says:  bash: alias: gnome-open ./Documents/the-linux-command-line.pdf; gnome-open ./Documents/linux.odt: not found   before even typing anything in, and when I run the command nothing happens, not even error messages. How to get a drive formatted with exfat working? In Ubuntu 13.04 there was an option to use the PPA by Relan in order to get ExFat functionality. Seeing that in Ubuntu this functionality is now available from the repositories without the PPA I tried this but failed to make it work.  So my question is how do I enable exfat support? Can you be tripped by an AoO while standing up? Suppose $f$ is a continuous single-variable function, prove that:  $$2\int_a^b \int_a^x f(x)f(y) \, dy \, dx = \left[ \int_a^b f(x) \, dx \right]^2$$  This question was just on my Calculus III final exam and I couldn't figure it out, could someone provide some insight, please? Simple way of finding the locus of $z$? I am tasked to sketch the locus of complex numbers $z$ that satisfies $$(z-2+i)^2 + (z^*-2-i)^2 + 2zz^* + 6 = 0$$ I was wondering if there’s a special trick to this question, or if this is only solvable by plugging in $z=x+iy$ ? I noticed that the second term is the conjugate of the first, and wanted to substitute $w = z-2+i$, however this gives me a complicated expression for $zz^*$ which makes it more confusing. Is there a trick I’m missing out? Thanks! Edit: I have already solved it through direct substitution (parabola intersecting real axis at $x=3$ and $x=-1$) but it took a good 5 minutes or so, expanding everything correctly, which seems rather long (I was attempting it under exam conditions). I was just wondering if it is possible to exploit the $w$ substitution I made in particular. I have a huge amount of 2D-coordinates, associated with a value, e.g.:    x   |   y   | value 27.50   52.15   12.51 61.83   13.32   57.56 36.23   21.83   41.73 40.46   85.67   25.20 ...   The data is not tabular and I Want the points between two data-points to be interpolated in some way (which way is not really clear, yet)  I want to preset the data as heatmap like this:   Is there any ready-to-use package for PSTricks or TikZ to do it? Noticing that the "Human Verification" image did not show, I found that the src, , shows that sstatic.net is giving an SSL vertificate for *.stackexchange.com.. Delete all but the most recent X files in bash Is there a simple way, in a pretty standard UNIX environment with bash, to run a command to delete all but the most recent X files from a directory?  To give a bit more of a concrete example, imagine some cron job writing out a file (say, a log file or a tar-ed up backup) to a directory every hour. I'd like a way to have another cron job running which would remove the oldest files in that directory until there are less than, say, 5.  And just to be clear, there's only one file present, it should never be deleted. Captured variable in a loop in C# I met an interesting issue about C#. I have code like below.  List&lt;Func&lt;int&gt;&gt; actions = new List&lt;Func&lt;int&gt;&gt;();  int variable = 0; while (variable &lt; 5) {     actions.Add(() =&gt; variable * 2);     ++ variable; }  foreach (var act in actions) {     Console.WriteLine(act.Invoke()); }   I expect it to output 0, 2, 4, 6, 8. However, it actually outputs five 10s.  It seems that it is due to all actions referring to one captured variable. As a result, when they get invoked, they all have same output.  Is there a way to work round this limit to have each action instance have its own captured variable? Docker ppa package for Ubuntu 19.10 Does someone knows if it exists some ppa packages source for the newest Ubuntu version 19.10 i had problem with that when i upgraded from Ubuntu 19.04 to 19.10 i didn't work? Unbounded continuous function on non-compact metric space Suppose $(S,d)$ is a non-compact metric space. Is it possible to construct an unbounded continuous function from $S$ to $\mathbb{R}$? If it is possible, please show the construction method :)  Here's my attempt to solve this problem: Because $S$ is not compact, we can find a neighborhood assignment function $N(x)$ so that a finite cover is not possible. Then each time we can find an uncovered point from the union of neighborhoods before, and change the function by $f(x):=max\{f(x),\text{a function which equals to the indice of this point at that point and gradually vanishes at further points from the selected point}\}$. However I'm concerned that while this function is unbounded, there may be some invalid points for this function (goes to infinity)...  EDIT: As I found out there is a duplicate question, however the elementary solution is not presented in that question, so I still wish to know about this problem. :) Restrictive vs Non-restrictive Relative Clause I have been facing hard time understanding meaning of "random sample" as well as "iid random variable". I tried to find out the meaning from several sources, but just got more and more confused. I am posting here what I tried and got to know:  Degroot's Probability &amp; Statistics says:     Random Samples / i.i.d. / Sample Size : Consider a given probability distribution on the real line that can be represented by either a p.f. or a p.d.f. $f$. It is said that $n$ random variables $X_1 , . . . , X_n$ form a random sample from this distribution if these random variables are independent and the marginal p.f. or p.d.f. of each of them is $f$. Such random variables are also said to be independent and identically distributed, abbreviated i.i.d. We refer to the number n of random variables as the sample size.   But one of the other statistics book I have says:       In a Random Sampling, we guarantee that every individual unit in the population gets an equal chance(probability) of being selected.   So, I have a feeling that i.i.d.s are elements that construct random sample, and the procedure to have random sample is random sampling. Am I right?   P.S.: I am very confused about this topic, so I will appreciate elaborate reply. Thanks. Shorter way to say "conversational partner" I'm looking for a proper English word to say "conversational partner".   Is "interlocutor" a word an average person would understand?  Are there any other words or shorter expressions which could describe a person you are having a conversation with, but who is not your friend and is basically unknown to you? Ubuntu 12.04 on Amilo LA1703 after istalling graphics doesn't start? Why are passports checked at the check-in counter, Immigration and even at the gate? I was wondering, why there are passport checks at the check-in counter, Immigration and even at the gate?    For example, I was at Istanbul flying to either UK or US. There's a security check at the check-in counter asking a bunch of questions about my immigration status - even more than the Immigration officer at the border. Also, at the gate, there's also Security officer checking my immigration status and passport asking the same questions.    I thought that would be the responsibility of an Immigration officer rather than some third party company?   The thing I'm curious the most is they don't even know which countries this passport can go to with or without visa. They have to go back to the counter and check with the system which takes a long time. I was wondering why they hire these kind of companies to slow down the process? #!/bin/bash - no such file or directory I've created a bash script but when I try to execute it, I get   #!/bin/bash no such file or directory   I need to run the command: bash script.sh for it to work.  How can I fix this?