I want to align my equations in such a way that every + and - are written in one row.  I want to do it like this:  \begin{align*} &amp;+ \left( \gamma^{r}_{y} \gammabar^{v}_{u} \gammabar^{x}_{s}  &amp;- \gamma^{r}_{y} \gammabar^{v}_{s} \gammabar^{x}_{u} \right) \\ &amp;- \lb \gamma^{r}_{y} \gammabar^{v}_{q} \gammabar^{x}_{s}  &amp;+ \gamma^{r}_{y} \gammabar^{v}_{s} \gammabar^{x}_{q} \rb \\ \end{align*}  Where \gammabar is a macro for \bar{\gamma}   But if I want to do that I get an error:  Extra } or forgotten \right \end{align*}  So does anybody know what's going on there?  So I want to align not only with one &amp;, but many &amp;'s.
My MWE:  \documentclass{report}  \usepackage{amsmath}  \begin{document}  \begin{align} y &amp;= a \\ =&amp; -2c_1\bar{z}_1^2 + 2\bar{z}_1\bar{z}_2 + 2\bar{z}_2 \left ( -\bar{z}_1 -c_2z_2 - \frac{3\epsilon}{2}\bar{z}_2 -\sigma_{2,1}\cos(x_1)\Delta x_1 \notag \right. \\ \left. &amp;- \sigma_{2,2}\Delta x_2 -\sigma_{2,3} \Delta u +c_2 \chi_2 \vphantom{\frac{1}{1}} \right ) - 2\gamma \sigma_{2,1}^2\cos^2(x_1) \Delta x_1^2 - \gamma \sigma_{2,2}^2 \Delta x_2^2   - 2\gamma \sigma_{2,3}^2 \Delta u^2 \end{align}  \end{document}   The error I get:  Extra }, or forgotten \right.   The expected result:
How do I display a decimal value to 2 decimal places? I'm kind of curious what kinds of criteria other people go through when selecting the correct answer to their questions.  Here's what I consider when selecting the answer to my question:   Is the answer objective?  It's easy to pick out biased answers.  Usually they involve a statement along the lines of "x sucks, you should ALWAYS use y." Do other members seem to support the answer?  Has it gotten a significant number of +1 posts or has it been voted up a number of times? Is the answer the most thorough?  Does it have an example?   With that said, there are a couple of BAD reasons to choose an answer in my opinion:   The answer is what you want to hear.  My biggest pet peeve is when somebody asks what ostensibly appears to be a valid question, but is really just a thinly veiled attempt to get someone to agree with them.  Thus, the question usually ends up showing a certain bias.  And guess which answer gets selected?  The one that confirms that bias. Nobody posted a better answer.  If you don't see a good enough answer, don't select one.   I'm sure there are a few things I'm leaving out, plus some of what I've said may be arguable.  What is everyone else's take on this? introduces  which will allow the introduction of new literal syntax based on existing literals (int, hex, string, float) so that any type will be able to have a literal presentation.  Examples:  // imaginary numbers std::complex&lt;long double&gt; operator "" _i(long double d) // cooked form {      return std::complex&lt;long double&gt;(0, d);  } auto val = 3.14_i; // val = complex&lt;long double&gt;(0, 3.14)  // binary values int operator "" _B(const char*); // raw form int answer = 101010_B; // answer = 42  // std::string std::string operator "" _s(const char* str, size_t /*length*/)  {      return std::string(str);  }  auto hi = "hello"_s + " world"; // + works, "hello"_s is a string not a pointer  // units assert(1_kg == 2.2_lb); // give or take 0.00462262 pounds   At first glance this looks very cool but I'm wondering how applicable it really is, when I tried to think of having the suffixes _AD and _BC create dates I found that it's problematic due to operator order. 1974/01/06_AD would first evaluate 1974/01 (as plain ints) and only later the 06_AD (to say nothing of August and September having to be written without the 0 for octal reasons). This can be worked around by having the syntax be 1974-1/6_AD so that the operator evaluation order works but it's clunky.   So what my question boils down to is this, do you feel this feature will justify itself? What other literals would you like to define that will make your C++ code more readable?    Updated syntax to fit the final draft on June 2011 If $r,s,t$ are prime numbers and $p,q$ positive integers s.t. $\text{lcm}(p,q)$ is $r^2s^4t^2$, then the number of ordered pairs $(p,q)$ is? If $r,s,t$ are prime numbers and $p,q$ are the positive integers such that LCM of $p,q$ is $r^2s^4t^2$, then the number of ordered pairs $(p,q)$ is?  My attempt to the solution:  Let $r^a s^b t^c$ be the LCM where $a=2,b=4,c=2$  Then the cases that arise are  I case   1) $p$ has $r^as^bt^c$ then there are a total of $(2+1)(4+1)(2+1)$ options  II case   1) $p$ has $r^as^b$ or $s^bt^c$,$r^at^c$ then there are total of $(2+1)(4+1)(2+1)(3)$ options.  The answers comes out to be $45*4$ but the answer is $45*5$. Which case am I missing? the largest integer $n$ for which $n+5$ divivides $n^5+5$? When we divide $n^5+5$ by $n+5$, we get a remainder $-620$, i.e., $n^5+5=K(n+5)-620$ , now how to proceed further? Wavy stream of liquid Why is information indestructible? I really can't understand what Leonard Susskind means when he says in the video  that information is indestructible.  Is that information that is lost, through the increase of entropy really recoverable?   He himself said that entropy is hidden information. Then, although the information hidden has measurable effects, I think information lost in an irreversible process cannot be retrieved. However, Susskind's claim is quite the opposite. How does one understand the loss of information by an entropy increasing process, and its connection to the statement “information is indestructible”.  Black hole physics can be used in answers, but, as he proposes a general law of physics, I would prefer an answer not involving black holes. Copy game data from one PS4 to another? How can I set the default terminal used in Unity?  I would like to use the Ctrl+Alt+T hotkey to start a non-default terminal. The default terminal is gnome-terminal.   Where can I change the default terminal value? Referencing bib files with spaces in the filename I am using a Mac with TeX Live and Mendeley for automatically generating .bib files, some of which have spaces in the file names. I would like to know how to reference such files from LaTeX as using "" or \ doesn't seem to work. How to disable a USB port in Windows (XP) and make it available only for charging? apt-get stuck at 0 [Connecting to us.archive.ubuntu.com] When I do upgrade it gets stuck here:  user@plato:~# sudo apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done Calculating upgrade... Done The following packages will be upgraded:   bind9-host coreutils cpio curl dnsutils libbind9-90 libc-bin libc-dev-bin   libc6 libc6-dev libcgmanager0 libcurl3 libcurl3-gnutls libdns100   libdrm-intel1 libdrm-nouveau2 libdrm-radeon1 libdrm2 libisc95 libisccc90   libisccfg90 libjasper1 liblwres90 libplymouth2 libsepol1 libssl-dev   libssl-doc libssl1.0.0 linux-libc-dev mime-support multiarch-support ntp   ntpdate openssl plymouth plymouth-theme-ubuntu-text python3-distupgrade   ubuntu-release-upgrader-core unzip 39 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. Need to get 16.0 MB of archives. After this operation, 12.3 kB of additional disk space will be used. Do you want to continue? [Y/n] y 0% [Connecting to us.archive.ubuntu.com (2001:67c:1562::15)] ░   When I do update it gets stuck here:  user@plato:~# apt-get update 0% [Connecting to us.archive.ubuntu.com (2001:67c:1562::14)] [Connecting to sec░   I'm able to ping us.archive.ubuntu.com just fine:  user@plato:~# ping us.archive.ubuntu.com PING us.archive.ubuntu.com (91.189.91.23) 56(84) bytes of data. 64 bytes from economy.canonical.com (91.189.91.23): icmp_seq=1 ttl=54 time=81.5 ms 64 bytes from economy.canonical.com (91.189.91.23): icmp_seq=2 ttl=54 time=81.5 ms 64 bytes from economy.canonical.com (91.189.91.23): icmp_seq=3 ttl=54 time=81.5 ms 64 bytes from economy.canonical.com (91.189.91.23): icmp_seq=4 ttl=54 time=81.4 ms ^C --- us.archive.ubuntu.com ping statistics --- 4 packets transmitted, 4 received, 0% packet loss, time 3004ms rtt min/avg/max/mdev = 81.425/81.528/81.582/0.355 ms   What can i do to fix this?    What I have tried so far.  I've tried following directions on this blog:   To force apt-get to use IPv4 exclusively   Create a file in /etc/apt/apt.conf.d/99force-ipv4 Add this line to newly created file Acquire::ForceIPv4 false; Apt-get will now use IPv4 exclusively How to redirect users to custom lostpassword page? Bounty-like facility for rewarding excellent questions Amongst the reasons for starting a bounty, one can select:     Reward existing answer      One or more of the answers is exemplary and worthy of an additional bounty.   Why not enable one to reward excellent questions in a similar manner? How does the Wizard spellbook work? How do I determine what spells are in my spellbook when creating a character? Do I simply have a spellbook with all Pathfinder spells? Or if I'm creating a level 6 wizard, do I start knowing all level 6 spells, and then have to learn the rest as I play the game? Let $f$ be a bounded measurable function on a set of finite measure $E$.  For a measurable subset $A$ of $E$, show that $\int_A f = \int_E f \cdot \chi_A$     Lemma: Let $f$ be a bounded measurable function on a set of finite measure $E$.  Suppose $A$ and $B$ are disjoint measurable subsets of $E$.  Then $\int_{A \cup B} f = \int_A f + \int_B f$.   My first approach was to view the problem like this utilizing the above lemma:  $$\int_E  f \cdot \chi_A = \int_{E\setminus A} f \cdot X_A + \int_A f \cdot \chi_A $$  I'm not really sure how the result follows from the above. Word for phrases that are examples of what they describe URL Rewriting of a query string in php When looking for the path to an executable or checking what would happen if you enter a command name in a Unix shell, there's a plethora of different utilities (which, type, command, whence, where, whereis, whatis, hash, etc).  We often hear that which should be avoided. Why? What should we use instead? Is it okay to have a multi-language deck? I want to buy a few booster pack from a local shop that only gets them in French. Is it generally acceptable to show up to a tournament with cards in different languages?