Manipulate freezing on large calculations
Plotting heat equation in a Manipulate expression
(clickable)  Mainad has a valid height and width, however it isn't shown like subad1/subad2. Which are in essence exactly the same! (just a different background image).  Firebug shows my div as greyed out for some weird reason. Replacing the contents of mainad with just some text doesn't solve the problem (problem isn't related to inner elements)..   What's going on?! :( How do I make Thunderbird open links in Chromium? I want to be able to click links in Thunderbird emails and have them open in Chromium (package name chromium-browser). Instead, they open in Firefox.  I have tried the following:   xfce preferred applications (Chromium is not listed, so I had to hunt down the executable) -- next time I run chromium, it complains that it is no longer the default browser. Telling Chromium to set itself as the default browser. Thunderbird opens links in Firefox. update-alternatives. It's already listed as an alternative at the same priority as Firefox. The "open web browser" app menu item opens Chromium. Thunderbird opens links in Firefox.   I have looked through the entire preferences gui in Thunderbird (but not the advanced config editor yet) and seen nothing that mentions what browser to open links in.  Please note that this is not Google Chrome. I hava Lenovo g580 laptop. I want to change disk to SSD drive, but I'm not sure if my laptop support SATA 3 (6Gbps).  I write following output:  dmesg | grep SATA [    3.190743] ahci 0000:00:1f.2: AHCI 0001.0300 32 slots 6 ports 6 Gbps 0x5 impl SATA mode [    3.199450] ata1: SATA max UDMA/133 abar m2048@0xd3617000 port 0xd3617100 irq 43 [    3.199455] ata3: SATA max UDMA/133 abar m2048@0xd3617000 port 0xd3617200 irq 43 [    3.518365] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) [    3.857921] ata3: SATA link up 1.5 Gbps (SStatus 113 SControl 300)   Is that means I Can use SSD disk in SATAa 6Gbps mode? Boot drops to a (initramfs) prompts/busybox 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? So I understand the concept of gravity, in that it's not actually a force, but more of a displacement in the spacetime grid. An object with a big enough mass will bend the spacetime, causing smaller objects to "attract" to it (not really, but good enough for what I am trying to figure out)   Ok so that makes sense, but what I am not understanding is, how come planets don't just get engulfed by the Sun? There must be something acting against the gravity for the planet to be a certain distance away from the sun. Am I not understanding this concept correctly? How can I check if an application is running from a batch (well cmd) file?  I need to not launch another instance if a program is already running. (I can't change the app to make it single instance only.)  Also the application could be running as any user. We know Euler formula:  $$ e^{ix}=\cos(x)+i\sin(x). $$  Does this formula work if we replace real number $x$ with complex number $z$? Can someone explain collection_select to me in clear, simple terms? java.sql.SQLException: Column count doesn't match value count at row 1 I am writing a bash script to look for a file if it doesn't exist then create it and append this to it:  Host localhost     ForwardAgent yes   So "line then new line 'tab' then text" I think its a sensitive format.  I know you can do this:  cat temp.txt &gt;&gt; data.txt   But it seems weird since its two lines. Is there a way to append that in this format:  echo "hello" &gt;&gt; greetings.txt I understand what the Chinese remainder theorem is. However I am not sure how to apply it to my question. Can someone explain please? Single quote within double quotes and the Bash reference manual In section 3.1.2.3  titled Double Quotes, the Bash manual says:      Enclosing characters in double quotes (‘"’) preserves the literal   value of all characters within the quotes, with the exception of ‘$’,   ‘`’, ‘\’, and, when history expansion is enabled, ‘!’.   At the moment I am concerned with the single quote(').  It's special meaning, described in the preceding section, section 3.1.2.2 is:     Enclosing characters in single quotes (') preserves the literal   value of each character within the quotes. A single quote may not   occur between single quotes, even when preceded by a backslash.   Combining the two expositions,    echo "'$a'"   where variable a is not defined (hence $a = null string), should print $a on the screen, as '', having it's special meaning inside, would shield $ from the special interpretation. Instead, it prints ''. Why so? MacVim -- how to make Ctrl+A go to beginning of line, Ctrl+E to the end of the line I'm trying to switch to MacVim as my main editor, and I'm liking it so far, except for one issue:  I got really used to the Mac shortcuts control-A to go to the beginning of a line, and control-E to go to the end of a line.  However, these two don't work in MacVim (control-A does something weird -- it seems to increase the last number in a line by 1 or something, and control-E seems to scroll down the screen by one line).  Any way to make these two shortcuts go to the beginning of a line / end of a line respectively instead? I have 2 monitors connected to a NVIDIA GeForce GTX 660:   Left is 1920x1080 via DVI (Samsung SyncMaster 2443BW) Right is 2560x1440 via DisplayPort and is set to Primary (Samsung SyncMaster SA850)   I often leave my computer running overnight (working on long render job, doing backups, etc) so I only power off my monitors manually. However, if I power off the primary monitor, it is disabled completely as if it were unplugged from the graphics card (i.e. icons are moved, open apps are moved and resized to fit on the new primary monitor). If I switch from DP to a DVI cable, this does not occur. It seems to be an issue when using DisplayPort.  Is there a way to disable the monitor from being disabled completely in Windows when I power it off physically?   I have found no relevant settings in either Windows Display settings, nor the NVIDIA control panel software.  Edit #1: I'm using an .  Edit #2: Here is a screenshot of my NVIDIA Control Panel v7.2.710.0:   Edit #3: Here are screenshots of my Monitor configuration:    Clicking on Advanced settings reveals a Generic PnP monitor running at 59 Hz? 60 Hz is the only other option available.    Here is my secondary monitor which is connected via DVI:    Edit #4: If I open the "Screen Resolution" configuration panel and power the monitor off (via the power switch), this is what is shown:    It looks like I disconnected the monitor from the video card. Is speed of light and sound rational or irrational in nature? Just as circumference of circle will remain $\pi$ for unit diameter, no matter what standard unit we take, are the speeds of light and sound irrational or rational in nature ?   I'm talking about theoretical speeds and not empirical, which of course are rational numbers. How does a lurker gain reputation to receive privilege for commenting? Changing color and fonts of itemize How can I change the font and color of a particular command in a LaTeX document?  For example I want all the text that follows the \item tag to be gray and the font should be different from the rest of the document , which i can specify ... Finding an angle within an 80-80-20 isosceles triangle The following is a geometry puzzle from a math school book. Even though it has been a long time since I finished school, I remember this puzzle quite well, and I don't have a nice solution to it.  So here is the puzzle:    The triangle $ABC$ is known to be isosceles, that is, $AC=BC$. The labelled angles are known to be $\alpha=\gamma=20°$, $\beta=30°$. The task is to find the angle labelled "?".  The only solution that I know of is to use the sine formula and cosine formula several times. From this one can obtain a numerical solution. Moreover this number can be algebraically shown to be correct (all sines and cosines are contained in the real subfield of the 36th cyclotomic field). So in this sense I solved the problem, but the solution is kind of a brute force attack (for example, some of the polynomials that show up in the computation have coefficients > 1000000). Since the puzzle originates from a book that deals only with elemetary geometry (and not even trigonometry if I remember correctly) there has to be a more elegant solution. Ignore .DS_Store and Icon files in a folder with Cocoa NSFIleManager Python Script to Add Fields to Feature Classes I have to try to add a field called 'Name' to a bunch of different feature classes using python, and then access the name of the feature class to fill in the field. I have no idea how to even start this! I know I need a loop but that's all I know.