I have route list as result of pgRouting with street names. How to get messages "Turn left", "Go along" etc ... Can pgRouting do this or I need some other source and which?
Would like to emulate google maps' driving directions functionality but use pgRouting instead. google's data over the project area &amp; scale is quite a bit off so we want to use our own transport network data in postGIS.  any hints?  thanks.
Real Numbers Raised to Imaginary Powers? What is a real number to the power of an imaginary or complex number? e.g. 3i. I have searched through sites about imaginary numbers, but none seem to say anything about imaginary indices. Examples and explanations would be appreciated. This problem is from Discrete Mathematics and its Applications  My question is on 9b. I know that the sign represents an element is a member of. (from book)  I know that the O with a slash across it is the empty set which &quot;is a special set that has no elements&quot;. From , I got that the empty set is a subset of all sets, meaning that every member of the empty set(nothing) is also a member of any other set. Based on all of this, for 9b, would {0} contain the empty set because it fundamentally has the elements that consist of the empty set(nothing) or does it physically have to have the empty set? Somebody asked me this question in a job interview and I replied that their joint distribution is always Gaussian. I thought that I can always write a bivariate Gaussian with their means and variance and covariances. I am wondering if there can be a case for which the joint probability of two Gaussians is not Gaussian? I install virtualBox on Ubuntu 16.04, but after install and create new virtual Host shows this error:     Kernel driver not installed (rc=-1908)      The VirtualBox Linux kernel driver (vboxdrv) is either not loaded or there is a permission problem with /dev/vboxdrv. Please install virtualbox-dkms package and load the kernel module by executing  modprobe vboxdrv       as root. If it is available in your distribution, you should install the     DKMS package first. This package keeps track of Linux kernel changes and   recompiles the vboxdrv kernel module if necessary.  where: suplibOsInit what: 3 VERR_VM_DRIVER_NOT_INSTALLED (-1908) - The support driver is not installed. On linux, open returned ENOENT.     How to address this modprobe vboxdrv error? I created the following script:  #!bin/bash cat &gt; Top10 &lt;&lt;EOF Linux Mint 17.2 Ubuntu 15.10 Debian GNU/Linux 8.2 Mageria 5 Fedora 23 openSUSE Leap 42.1 Arch Linux CentOS 7.2-1511 PCLinuxOS 2014.12 Slackware Linux 14.1 FreeBSD EOF sed -ri "s/^[^0-9]*$//" Top10 sed -r "s/(.*)([[:space:]][[:digit:]]*.*)$/\2\1/" Top10 | sed -r "s/([[:space:]])([[:digit:]])/\2/" | sed -r "s/([[:digit:]])([[:alpha:]])/\1 \2/" &gt; Top10 sed -r -i "s/(.*)/\L\1/" Top10 sed -r -i "y/[aeiou]/[AEIOU]/" Top10 sort Top10 -g -o Top10 cat Top10   When I run it a few times the following happens:     As you can see sometimes the Top10 file turns out empty and sometimes it turn out the way I needed it to be. I know that the command which replaces the extensions from the end to the front of a line is done poorly. I ran this script on a VMware virtual machine. Could that be the reason? My ListView (of my ViewFilipper) fills the parent and buttons on the bottom get hidden Improve file-info visibility in Finder's preview pane I find the file information in the preview pane in column view is far more useful than the thumbnail.  I wish I did not have to continually resize the Finder window or scroll the preview pane to see the info I'm looking for.  As you can see below, the useful info is hidden in default  size  of Finder's new window under the preview options like rotate etc.        Is there a way to do any of these to achieve the said goal (listed in order of decreasing likelihood!):   reduce the size of the preview "thumbnail" covered by black here,  reduce the amount of whitespace(grey here) around the preview "thumbnail" (only significant for landscape thumbnails), remove the preview "thumbnail" altogether,  reorder the content of the preview column(bring file info up and send thumbnail down)?    includes the options:   resizing the Finder in every new window (which is labor intensive). Using View menu> Show Preview Options to turn off Quick Actions (which must be done for each file-type, and only reveals a small amount of file info). How do you style an input type="file" button? Crossfading Video AND Audio with ffmpeg This Super User answer  has got me so far, but now that I have tried many solutions and seen every SO link out there, it's time to ask you all for help.  I am trying to crossfade 2 videos that are 10 seconds each in ts format with audio and video at the same time.   The steps are:   Add complex filter black screen Fade out video 1 after 9 seconds, with 1 second fade duration Fade in video 2 at 9 seconds, with 1 second fade duration Trim black filter output to 19 seconds   This works fine for just video alone, but when I attempt to add audio, I can't get past this error message:     Output pad "default" with type audio of the filter instance "Parsed_asetpts_4" of asetpts not connected to any destination   It appears I'm not connecting the audio output properly. I think I need to alter the [over] lines to include audio. But how do I do this?  `ffmpeg -i vid1.ts -i vid2.ts -f lavfi -i color=black -filter_complex \ "[0:v]format=pix_fmts=yuva420p,\ fade=t=out:st=9:d=1:alpha=1,setpts=PTS-STARTPTS[v0];\ [0:a]\ afade=t=out:st=9:d=1,asetpts=PTS-STARTPTS[a0];\ [1:v]format=pix_fmts=yuva420p,\ fade=t=in:st=0:d=1:alpha=1,setpts=PTS-STARTPTS+9/TB[v1];\ [1:a]\ afade=t=in:st=0:d=1,asetpts=PTS-STARTPTS+9/TB[a1];\ [a0][a1]amix=inputs=2;\  [2:v]scale=720x406,trim=duration=19[over];\ [over][v0]overlay[over1];\ [over1][v1]overlay=format=yuv420[outv]" -vcodec libx264 -y -map [outv] final.ts` Let's assume that one has some modern HP printer and/or scanner which is not supported by HPLIP package from official repository. Currently Ubuntu versions have :  trusty (14.04LTS): 3.14.3-0ubuntu3.4 xenial (16.04LTS): 3.16.3+repack0-1 bionic (18.04LTS): 3.17.10+repack0-5 focal (20.04LTS): 3.20.3+dfsg0-2 groovy (20.10): 3.20.5+dfsg0-3build1 hirsute (21.04): 3.21.2+dfsg1-2   What can one do if printer is supported in newer version of HPLIP (checked this in )? How to customize the_archive_title()? Code snippet comments in code formatting break the formatting of the post Problem with \printindex. No index created I tried to create an index to a document I write, but when viewing the .pdf output there was no index. Also no error messages were displayed. I managed to find this in the LOG FILE: No file "Actual Document".ind. ("Actual Document.aux") ) Indeed, when I check the folder supposed to have these files, I found only a file Actual Document.idx with all my indices, but no .ind file. Changing the extension .idx to .ind produced an error. Here is what I have written:  \documentclass[12pt]{book} \usepackage{makeidx} \makeindex \begin{document} continuous \index{continuous} \clearpage \printindex \end{document}   What have I done wrong and what is going on with these files? Bad Eyesight and Evolution Why do many humans have bad eyesight, such as near-sightedness, which hampers performance in a wide variety of tasks? Shouldn't there be evolutionary pressure towards better eyesight? Period character used for local computer name I'm wondering about the period character . used as a shortcut for the local computer name.  You can use it when logging into Windows 7, for example, to specify that the user account you're entering belongs to the local computer rather than to a domain:  .\MyLocalUserAccount   And you can use it within a Windows Management Instrumentation (WMI) query to indicate that the target is the local computer rather than a remote computer.  You can also use it when working with named pipes to for similar purposes.  However, you cannot use it as the UNC network name for the computer, like this:  \\.\MyShare   Does this character have an official name (e.g. "LocalHostToken") and when and where can it be used for this purpose? Is there a constraint that restricts my generic method to numeric types? What amp rating of 24vac transformer for LM317T? I want to know what size transformer for LM317 at full 30 VDC. I know its a 24 VAC center tapped transformer but is 1 A or 5 A transformer best suited for a linear power supply of 1.5-30 VDC?  I will be using a standard LM317 variable power supply circuit with the 2200 uF 50 V smoothing and the 240 ohm drain resistor and potentiometer. I have a homemade oversized aluminum heat-sink that is quite large. Can my spouse receive an emergency UK visa to visit a funeral? I'm a British national. My grandmother just passed. My wife is Chinese. In general it's a major pain to get my wife a visa to visit the UK, we have never been before.  Is there any way to get an emergency visa to attend the funeral?  What sort of documents would we need? I need to generate random numbers within a specified interval, [max;min].  Also, the random numbers should be uniformly distributed over the interval, not located to a particular point.  Currenly I am generating as:  for(int i=0; i&lt;6; i++) {     DWORD random = rand()%(max-min+1) + min; }   From my tests, random numbers are generated around one point only.  Example min = 3604607; max = 7654607;   Random numbers generated:  3631594 3609293 3630000 3628441 3636376 3621404   From answers below: OK, RAND_MAX is 32767. I am on C++ Windows platform. Is there any other method to generate random numbers with a uniform distribution? Inequality vs. Inequation, Equation vs. Equality When talking about statements that two terms are mathematically (un-)equal (e.g., 1 = 1, 1 &lt; 2, or 1 != 2), what is the correct notion for such mathematical statements? Are there special cases w.r.t. "mixed" relations like x &lt;= y? Can some notions be used interchangeably?  It seems many online sources use "equation" and "inequality" but there is also a . Apart from personal posts in forums, I have not found any sources using "equality" in such a situation, yet. Systematically, I would think that "equation" and "inequation" would make more sense than "equation" and "inequality", but not everything (probably very few things) in natural languages have developed according to a purely logical system.  Note that this question is more general than  for that it particularly asks for the relation between the notion for equations and the one for inequalities. Equations are not part of the existing question at all.