Is there a way to install apps in ubuntu 12.04? What I am looking for is something like an *.msi file for windows. If there isn't, then is there a way to enable all software resources so that you could just install an app by clicking on the install button in the SC? I am not concerned about viruses, as I can just wipe the partition and re install ubuntu, no personal files are stored on the computer.
How can I install applications like Google Chrome on Ubuntu?  Are there any commands to install an application?    Index of answers:
I am using Ubuntu 11.10 (64 bits) and I do not want to mount automatically USB thumb drives in my system. I tried the command dconf-editor and gconf-editor but there isn't the icon to disable it in nautilus preferences (apps|nautilus|preferences|media_automount).  Thanks. What's the difference between "Service" and "/etc/init.d/"? I'm asking this because my HDD (Hard Disk) has 5 years, and ultimately (this year) it gave me many headaches. Many moths ago I has Windows 7 (and 10 T.P. since april) and all was good. But after a moment, instantly, all gets reversed: veeery slow, and actions which will take a tiny time, at these moment the time seems frozen (for example, instead a 1 minute boot, it turned to 5-8 minutes boot). I formatted and installed Windows every 2 months because it was the time which runs good before it gets slooww. Seeing the abuse of privacity in W10, I changed to Ubuntu 15.04 and the things lasted more in time... But again, HDD error. Click, trying to read, click, trying to read... And the upper bar (title of window/buttons of volume, language, wifi, etc.) disappeared. The left bar (where are the app's icons) was empty and the file explorer said the resource wasn't available (or something like these error). I restarted and nothing happens. I had to press CTRL+D to boot-up Ubuntu, but after hours... the same error (can't do anything except moving the mouse/cursor).  Welcome to the routine: copy files with live-cd to a pendrive, wipe HDD and install all again. And the things was calmed again... and the errors comes again. And after 2 weeks, I had to do the same. Now my PC works fine, but yesterday I heard a few "clicks" from the HDD.  Now, I remembered this  and I came to Disks and the HDD shows a new value; normally, the problematic number was "pending sectors", always changing, but now, in "irrecoverable sectors", the number is different of zero.  I never had "reallocated sectors". Now, neither. And now, while I write this lines, I've 5 "pending s." and 9 "irrecoverable s.". If this helps, the "read error rate" is 42, 5 for "write error rate".      Very well!! While I was writing "write error rate", I heard 2   clicks. And while writing this, one click more.   And 123 "CRC error rate". So, with this information: is my HDD dying? It'll last days or months? I think this problem will kill the disk in a not very far time.  The drive is a Western Digital Green 1TB-WDC WD10EARS-00Y5B1 (80.00A80) S.N.: WD-WCAV5J301610  PS: When I boot with CTRL+D, many times the system is in "RO mode"; I can't save/download files, Unity doesn't find apps when I write their name {click again, now, while I write the text} and, after a few hours, a crash like the lines above I play D&amp;D 5e and sometimes come here with questions. But sometimes I see things referenced here as sources that I don't have or aren't aware of....  Which are the "official rules" for D&amp;D 5e, and where do I find them? Using SQLite3 with Python 2.5, I'm trying to iterate through a list and pull the weight of an item from the database based on the item's name.  I tried using the "?" parameter substitution suggested to prevent SQL injections but it doesn't work. For example, when I use:  for item in self.inventory_names:     self.cursor.execute("SELECT weight FROM Equipment WHERE name = ?", item)     self.cursor.close()   I get the error:     sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and there are 8 supplied.   I believe this is somehow caused by the initial creation of the database; the module I made that actually creates the DB does have 8 bindings.  cursor.execute("""CREATE TABLE Equipment      (id INTEGER PRIMARY KEY,      name TEXT,     price INTEGER,      weight REAL,      info TEXT,      ammo_cap INTEGER,      availability_west TEXT,     availability_east TEXT)""")   However, when I use the less-secure "%s" substitution for each item name, it works just fine. Like so:  for item in self.inventory_names:     self.cursor.execute("SELECT weight FROM Equipment WHERE name = '%s'" % item)     self.cursor.close()   I can't figure out why it thinks I have 8 bindins when I'm only calling one. How can I fix it? Making sense of principal component analysis, eigenvectors & eigenvalues How does Ethernet know how long a frame is? What is the difference between "used space", "size" and "size on disk"? There is only one partition for both system files and personal data, which is C:. The other two partitions are for boot and for recovery.  Now I have two different reports on the size of C: on my Windows 7:   by clicking the property of C:, it shows 59.4 GB for "used space"; by selecting all contents (I have setup to view all hidden files and directories) under C: and viewing their property, it shows 46.9 GB for "size" and 47.6 GB for "size on disk".   Here are my questions:   I was wondering why the two reports are not the same, and where the difference comes? in the second way, why "size" and "size on disk" are different? What do they mean actually? What is the difference between them and "used space" in the first way?   Thanks in advance! Regular expression to extract text between square brackets Geometric series and big theta Consider the following function:  $$S(n)=1+ c + c^2 + ··· + c^n,$$  where c is a positive real number.  (A) This function is the sum of a geometric series. Give a precise closed-form formula for $S(n)$, interms of $c$ and $n$, in the case where $c \neq 1$.  (B) Show that $S(n)$  is:  $\theta(1)$ if $c&lt;1$  $ \theta(n)$ if $c=1$  $\theta(c^n)$ if $c&gt;1$    can someone please explain how i can go about finding the solutions for these problems, i have never encountered these and am stuck, i know that big theta means that the function is bond on both sides but how do i got about finding the answer?  (edit) im still having trouble understanding part B. can someone please explain? (can someone walk me through the second one) so far i have $n \leq c^{n+1} \leq ???$  (edit #2) i tried doing the first one can someone verify if i did it right  $S(n)$ is $\Theta(1)$ if c&lt;1  (1)$S(n)$ is $O(1)$ if c&lt;1  (2)$S(n)$ is $\Omega(1)$ if c&lt;1  (1) $$\frac{C^{n+1}-1}{C-1} \lt (C_1)(1)$$ $$\frac{C^{n+1}-1}{C-1} \lt (C_1)$$ $$C^{n+1} \lt C_1(C-1)$$ $$C^nC-1 \lt C_2C-1$$ $$C^n \lt C_2$$ $$C^n \lt 1$$ since c&lt;1 this means that any number that will be $C^n$ will be less then 1 for all positive n  i did the omega part pretty much the same way and got $$C^n \gt C_2$$ $$C^n \gt 0$$ since c&lt;1, $C^n$ can potentially become very very small so the only thing bounding it is 0 for all positive n I was thinking of how to create an IV for a block cipher that doesn't require stored state, and I came up with the idea of using an HMAC of the (padded) plaintext and a (possibly distinct) key as the IV.  This seems to be secure:   The IV will only be reused if there is an HMAC collision or if the plaintext and key are the same.  The former would imply that the HMAC is broken and the latter is harmless, since it is just producing the output twice. The HMAC is verified after decryption, but before padding is checked, so padding-oracle attacks should not be an issue.   In particular, if the HMAC and the block cipher use different keys, there seems to be a very simple proof of security, assuming that either (1) the HMAC cannot be distinguished from a random function or (2) the block cipher is secure against maliciously-chosen (but unique) IVs:   The attacker cannot forge the HMAC, since this would require knowledge of the signing key. Since the signing and encryption keys are different in this case, and the HMAC is assumed random, malicious IVs cannot be triggered by an attacker.   Alternatively, if the cipher is secure against malicious (but unique) IVs, then the security of the cipher+security of the HMAC seem to prove the security of the system.  This (obviously) provides no protection against replay attacks, but that requires state anyway.  However, I am not a cryptographer so I do not trust my conclusions on this matter.  If this technique is secure, it would appear to be quite useful in practice, as it is simple and provides both encryption and authentication. How to set class weights for imbalanced classes in Keras? Story about a sentient star system, in a 50s or early 60s anthology Story about a sentient star system, possibly in f&amp;sf anthology from 50s or early 60s. I know this is a long shot, but I hope someone will know of this story.  I believe it was called "Darkness or into the darkness". End of the story had it spinning off a galaxy, (possibly ours?). Divisibility Rule for 9 I'm working through an elementary number theory course right now and I think I've come up with a proof here but wanted some feedback on my logic.    Question:  If the sum of the digits in base 10 is divisible by 9, then the number itself is divisible by 9.    Proof: Suppose that $9|d_1+d_2+...+d_n$ then $d_1+d_2+...+d_n=0\mod9$  Now consider $d_1(10^{n-1})+d_2(10^{n-2})+...+d_{(n-1)}(10^1)+d_n(10^0)$ Each power of $10$ is equivalent to $1\mod9$   therefor  $d_1(10^{n-1})+d_2(10^{n-2})+...+d_{(n-1)}(10^1)+d_n(10^0)=(1\mod9)(d_1+d_2+...d_n)$  $9|(d_1+d_2+...d_n)$ by our assumption, thus $9|(1\mod9)(d_1+d_2+...d_n)$  Thus we have shown that if 9 divides the sum of the digits in base 10, 9 divides the number itself.    The only question I really have is whether I'm jumping the gun on my assumption concerning the powers of 10 being $1\mod 9$.  I think this is fair game here but not 100% confident.  Thanks. One of the joys of high-school mathematics is summing a complicated series to get a “closed-form” expression. And of course many of us have tried summing the harmonic series $H_n =\sum \limits_{k \leq n} \frac{1}{k}$, and failed. But should we necessarily fail?      More precisely, is it known that $H_n$ cannot be written in terms of the elementary functions, say, the rational functions, $\exp(x)$ and $\ln x$? If so, how is such a theorem proved?    Note. When I started writing the question, I was going to ask if it is known that the harmonic function cannot be represented simply as a rational function? But this is easy to see, since $H_n$ grows like $\ln n+O(1)$, whereas no rational function grows logarithmically.  Added note: This  asks a similar question for “elementary integration”. I guess I am asking if there is an analogous theory of “elementary summation”. Yet another "inconsistent reputation history" Convert and redirect URL in uppercase to lowercase using .htaccess I would like to redirect a URL with uppercase characters http://localhost/A/B to a lowercase version http://localhost/a/b using the .htaccess file. Using regex I can capture A and B but is it possible to convert them to lowercase? Factorial identity $n!=1+(1-1/1!)n+(1-1/1!+1/2!)n(n-1)+\cdots$ Show that $\displaystyle{n!=1+\left(1-\frac1{1!}\right)n+\left(1-\frac1{1!}+\frac1{2!}\right)n(n-1)+\cdots}$. I can't figure out how this can be solved. I tried to use the binomial theorem but I couldn't prove it. Any help will be greatly appreciated. If a subring of a ring R has identity, does R also have the identity? I know it does not make sense that if a subring of a ring $R$ is commutative, then $R$ is also commutative. (For example, the set consisting of the matrices whose all entries except (1,1)-entry are zero, is a subring of ring of 2x2 real matrices.)  I also considered the case of a ring containing a subring with identity, but I had no ideas. Maybe it seems that it does not make sense, either.  Who give me some examples supporting my guess? How to specify that search should be between two dates in technical specification I'm writing an integration manual that specifies how to use our WCF service for mobile messages and responses. The part in question needs to specify that the search results will be filtered between the start and end dates.  My aim is to make it clear that the time portion of the two dates will be discarded and the result will include everything from the start date to the end date. (In practice the code truncates the dates, adds one day to the end date, and returns the data that conforms to a query something like:  SELECT * FROM Table WHERE DateCreated >= @StartDate AND DateCreated &lt; @EndDate)  But my paragraph looks verbose and clumsy. It doesn't feel right. I feel kind of like John Cleese telling the kids when to put their clothes onto a lower peg. How can I make this less verbose?  Or maybe I'm over-thinking this?     When searching for responses, the search is performed between the supplied dates, after truncating the time portion thereof. The results will include responses with a date-time greater than equal to the start date, and less than one day after the end date. So passing the same value for start and end date will retrieve all responses received on that date, for messages previously sent by that user.