Trying to download an audio from youtube.  youtube-dl --extract-audio --audio-format mp3 https://www.youtube.com/watch?v=ILSr9BbhoJQ [youtube] ILSr9BbhoJQ: Downloading webpage [youtube] ILSr9BbhoJQ: Downloading video info webpage ERROR: ILSr9BbhoJQ: "token" parameter not in video info for unknown reason; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.   Then I did this.  sudo apt-get remove youtube-dl sudo mkdir -pv /usr/local/bin sudo wget https://yt-dl.org/downloads/latest/youtube-dl -O /usr/local/bin/youtube-dl sudo chmod a+rx /usr/local/bin/youtube-dl   andy@7_~/Downloads$ youtube-dl -U bash: /usr/bin/youtube-dl: No such file or directory   youtube-dl is in /usr/bin directory.
After uninstalling a program with apt and reinstalling it in another location (ex. pypy with snap), running the program from command line reports bash: /usr/bin/pypy: No such file or directory, but which pypy correctly gives /snap/bin/pypy. How do I get the shell to recognize the new installation location?
calculating mean of a random variable raised to a power Question on groups of order $pq$ Let $G$ be a group of order $pq$, $p&gt;q$  and $p$, $q$ are primes. Then prove that  If $q\mid p-1$ then there exists a non abelian group of order $pq$. Any two non-abelian groups of order $pq$ are isomorphic.   I have proved that if $q\not\mid p-1$ then $G$ is cylic . But how to prove this one I have no idea. Any kind of hint is very much welcome. This problem is in Herstein book, page 75. I know only the very basics of TikZ, having only used it to produce a pretty flow chart for one of my documents. I recently learned that you can use Inkscape and export to TikZ.  What are the limitations of the Inkscape->TikZ workflow? Is there some compelling reason to take the time to learn TikZ (which I'm told has a fairly steep learning curve) rather than simply exporting to TikZ from Inkscape? Is Ubuntu an open source software? Function returns None without return statement Placement of question mark when terminal quote has no question mark but sentence does Possible Duplicate:          If I'm quoting something someone said and the quote does not have a question mark, but I want to end the sentence with a question mark, would it be     Are you sure she said "Spicy?"   or       Are you sure she said "Spicy"? Why does the collada exporter not export texture references? I've been having trouble exporting collada objects from blender, so I stripped everything back and textured a single cube, and exported it.  This is a completely trivial model, one cube, with one material assigned to it, the material has a single 'g.png' texture assigned to it.   The exported collada data looks like this:    &lt;library_materials&gt;     &lt;material id="Material-material" name="Material"&gt;       &lt;instance_effect url="#Material-effect"/&gt;     &lt;/material&gt;   &lt;/library_materials&gt;   Where:    &lt;library_effects&gt;     &lt;effect id="Material-effect"&gt;       &lt;profile_COMMON&gt;         &lt;technique sid="common"&gt;           &lt;phong&gt;             &lt;emission&gt;               &lt;color sid="emission"&gt;0.2879998 0.2879998 0.2879998 1&lt;/color&gt;             &lt;/emission&gt;             &lt;ambient&gt;               &lt;color sid="ambient"&gt;0 0 0 1&lt;/color&gt;             &lt;/ambient&gt;             &lt;diffuse&gt;               &lt;color sid="diffuse"&gt;0.2163267 0.1845119 0.2121569 1&lt;/color&gt;             &lt;/diffuse&gt;             &lt;specular&gt;               &lt;color sid="specular"&gt;0.5 0.5 0.5 1&lt;/color&gt;             &lt;/specular&gt;             &lt;shininess&gt;               &lt;float sid="shininess"&gt;50&lt;/float&gt;             &lt;/shininess&gt;             &lt;index_of_refraction&gt;               &lt;float sid="index_of_refraction"&gt;1&lt;/float&gt;             &lt;/index_of_refraction&gt;           &lt;/phong&gt;         &lt;/technique&gt;         &lt;extra&gt;           &lt;technique profile="GOOGLEEARTH"&gt;             &lt;double_sided&gt;1&lt;/double_sided&gt;           &lt;/technique&gt;         &lt;/extra&gt;       &lt;/profile_COMMON&gt;       &lt;extra&gt;&lt;technique profile="MAX3D"&gt;&lt;double_sided&gt;1&lt;/double_sided&gt;&lt;/technique&gt;&lt;/extra&gt;     &lt;/effect&gt;   &lt;/library_effects&gt;   This seems to be missing the texture data associated with the object.   By comparsion, exporting a wavefront object generates this .mtl file:  # Blender MTL File: 'basic.blend' # Material Count: 1  newmtl Material Ns 96.078431 Ka 0.000000 0.000000 0.000000 Kd 0.790000 0.790000 0.790000 Ks 0.500000 0.500000 0.500000 Ni 1.000000 d 1.000000 illum 0 map_Kd g.png   &lt;----- ie. Blender is aware of this texture   So... is the collada exporter for blender just broken, or does it require some kind of special config in order to function correctly?  If the latter, how/what is required to make this work?  (NB for what it's worth, the UV coordinates are exported in the .dae, abit they obviously are completely useless without a texture assigned to them; I've also tried adding two different textures to see if the exporter needs that because it naively assumes 'one texture = don't bother, it's one texture for the whole model'. That didn't work either) The label toolbar uses fields in the attribute table of vector layers to fine tune labeling (Data defined labeling). That's the main reason i'm looking for that, but it may have more applications.  I'd like to automatically add some format columns instead of adding them manually every time.   Do you know a plugin or a way to do this manipulation automatically on multiples layers ?  I tried to get the QGIS tool "Add a field to attribute table" into a quick model which works properly, but it creates a new memory layer. And I'd like just new fields.  ##Add_ETIKT_Field=name ##myvlayer=vector ##myvlayer=output vector outputs_QGISADDFIELDTOATTRIBUTESTABLE_2=processing.runalg('qgis:addfieldtoattributestable', myvlayer,'ETIKT_Y',1,15.0,4.0,None) outputs_QGISADDFIELDTOATTRIBUTESTABLE_1=processing.runalg('qgis:addfieldtoattributestable', outputs_QGISADDFIELDTOATTRIBUTESTABLE_2['OUTPUT_LAYER'],'ETIKT_X',1,15.0,5.0,myvlayer)   What I'm looking to automate is :   Open the attribute table Edit button Field Calculator button Add Column + Type + length + Precision   It seems there's some ideas in , but I'd love to avoid coding anything, or at least at minimum go through the modeler.     Adding and Removing Fields       To add fields (attributes), you need to   specify a list of field definitions. For deletion of fields just   provide a list of field indexes.   if caps &amp; QgsVectorDataProvider.AddAttributes:     res = layer.dataProvider().addAttributes([QgsField("mytext", QVariant.String), QgsField("myint", QVariant.Int)])  if caps &amp; QgsVectorDataProvider.DeleteAttributes:     res = layer.dataProvider().deleteAttributes([0]) Why can't I extend this partition into the unallocated space? Why are there directories called Local, LocalLow, and Roaming under \Users\\AppData? I have a workstation running Windows Server 2008 that's logged into an  domain, and I have a dual boot with Ubuntu Linux. When running Linux, I'd like to be able to use the same Thunderbird profile I use under Windows, so I pointed Thunderbird to use a profile I found under:  \Users\(myname)\AppData\Local\Thunderbird\Profiles   It turns out it was not the correct profile -- it had the right configuration, but the Inbox was an old version. I eventually found out the correct path was:  \Users\(myname)\AppData\Roaming\Thunderbird\Profiles   What's the rationale behind those different places to store application data? How to get access to USB-storage from an application installed as Snap? I wanted to remove and reinstall the software-center package.  I removed it, but now I can't reinstall.  I tried these commands without success:  sudo apt-get update sudo apt-get install software-center   How can I reinstall software-center?    When I performed the install command this is what I got:  $ sudo apt-get install software-center Reading package lists... Done Building dependency tree        Reading state information... Done Package software-center is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'software-center' has no installation candidate Intuitive explanation for dividing by $n-1$ when calculating standard deviation? I'm trying to make a map using the Javascript API.  I want to use my own basemap, but I can't find the most simple code to do this.  I always see something like this:    function init() {     map = new esri.Map("mapDiv", {       basemap: "satellite",       center: [-97.395, 37.537],       zoom: 11     });   But I don't want to use the ArcGIS online basemaps.  What is the code to make a map service I am hosting my basemap? Validationengine jquery not working properly for localization Content Type field on NewForm.aspx I have a custom list and I am using content types to add items to the list. I am using OOTB forms for new and edit items. One field that I see on the EditForm.aspx is the one that I hope I get on the NewForm.aspx also and it is the Content Type field. It is shown in the following screenshot. Do you know how to add that field on the NewForm.aspx page also?    Thanks. Consider a string under tension, for example, a string on a guitar. When a guitar string is plucked, it vibrates at a certain frequency. When the tension on the string is increased by twisting the tuning peg at the end of the neck, the frequency of the string increases. According to , increasing the tension on a string also increases the speed of the wave moving through it. According to  the speed of a wave is higher in a more dense medium.  Does this mean that increasing the tension also increases the density?  This does not seem very logical to me, since density is the "compactness" of a substance, or how close together the individual molecules are. By twisting the tuning peg on a guitar, you rotate the cylinder that the string is fixed to, wrapping it around more tightly. This pulls more of the string around that cylinder, similarly to when you reel in a fishing rod. Since more of the string's molecules are now wrapped around the peg, there should be fewer molecules over the same distance between the bridge and the nut (the two ends of the vibrating portion of the string), therefore bringing the density down. Strange bar plot alignment in Pandas Complete local ring which is not complete valuation ring Complete valuation ring is obviously complete local, because valuation ring is always local ring. I would like to know the example of  Complete local ring which is not complete valuation ring  Any examples? I could find example of local ring which is not valuation ring, but the example ring is not complete. Thank you for your help. I recently read a lot about neural networks using GRU or LSTM units. There are many easy to use frameworks like tensorflow that do not even require high knowledge about programming. Unfortunately, I never really found good information on how the training of those networks work. Simple backpropagation might probably not work for gated recurrent networks or is just too inefficient for networks with such a high number of variables to learn.  So my question is:  What are the state-of-the-art algorithms used for the initialization and training of neural networks with GRU or LSTM units? I am not looking for frameworks to use, but for initialization and update equations for the internal parameters.