NullpointerException with javafx even if object present?
What is a NullPointerException, and how do I fix it?
Proof that the largest eigenvalue of a stochastic matrix is $1$ What font is "z" in "z-score"? The following  (links to pdf) in the  has no provided source. The book  by Ash and Gross seems to use a similar style. Where can I find hints for typesetting publication standard articles/books as above in TeX. I looked around a bit but couldnt find much from else from keyword searches.  Particularly, I am looking at the chapter headings, title page design, and the mirror effect. Sorry for the title, as I dont really know what its called. VMware Linux Server -- how can you tell if you are a vm or real hardware? An interesting question.  I have logged into a Linux (most likely SuSE) host.  Is there some way that I can tell programmatically that I am a VM host or not?    Also assume that the vmtools are not installed. Why does Earth behave like Natural Bar Magnet? What is the reason for the Earth to behave like a bar magnet and have poles (North and South poles)? Working on a future method to post values to external web service. But since there is a limit of 50 callouts per invocation, I am getting error "Too many future calls : 51". Cases are loaded into salesforce from external ETL in bulk. So is there a way to workaround this error.   Class  public with sharing class caseTrigger {      //method invoked by trigger after insert     public void CaseInsert(List&lt;Case&gt; caseIns){           list&lt;Id&gt; caseIds = new list&lt;id&gt;();             List&lt;Case&gt; caseList = [Select id from case WHERE Id IN :caseIds];                 for(Case c : caseList){                     if(c.Status != 'closed'){                         caseIds.add(c.id);                     }                          if(f.caseId_User.size()&gt;0){PostCases(caseIds);}      }     //postCases (future method)     @future(callout = true)     public static void PostCases(List&lt;Id&gt; Ids){         //prepare Json to post to webservice    } } Filter "Hot Network Questions" by excluding sites Replacing ArcPy with ArcGIS API for Python? Today I found out about the . I was wondering if you could use this to (eventually) replace ArcPy?  Recently I have been doing analyses that require cloud based solutions. When using AWS, Docker and Jupyter it is very convenient to stick with a Unix based OS such as Ubuntu. However, the Unix alternatives for ArcGIS have their own limitations as well such as the always hard to install python bindings for the  GDAL library. ArcGIS for Python operates cross platform.  Perhaps there are the things I should and should not expect from the ArcGIS API for Python.  Perhaps Arcpy is going to disappear altogether. Quadratic substitution question: applying substitution $p=x+\frac1x$ to $2x^4+x^3-6x^2+x+2=0$ By using the substitution $p=x+\frac{1}{x}$, show that the equation $$2x^4+x^3-6x^2+x+2=0$$ reduces to $2p^2+p-10=0$.  I can't think of anything that produces a useful result, I tried writing p as $p=\frac{x^2+1}{x}$ and finding areas to substitute but have come with no progress. Could someone offer a slight hint on how to proceed?  Thanks What is the VTable Layout and VTable Pointer Location in C++ Objects in GCC 3.x and 4.x? Can't open a folder in windows 7 64bit, by double clicking, it shows me that the default option for opening folder is "cmd" (it's highlighted when i'm right clicking a folder, and the "open" option comes next). I've tried running some registry fixing tools, but it didn't fix it. Can someone suggest me what should I do. Due to my reputation on Stack Overflow, I have access to different review queues. I want to know if it will change my score/reputation or if it will only provide me some badges?  Maybe this part seems a bit odd, but I want to know why some users spend so much time in the review queues? Is it something about their passion about Stack Overflow or their passion to help others inside the community or does it have some other reasons which I've missed?  P.S. I have read some information like  and  but I will be grateful to have your answer about this. Why are there not generic phone OS installers? I made a skin by using Skincraft and I exported it to minecraft.net. I chose my skin and uploaded it. At the top it says,      "Your skin has been changed! Please wait a few seconds for it to   update."   I went to Minecraft, clicked singleplayer and chose a random world at the top. I looked at my character, but it's still default. Multiplayer won't load for some reason. I don't know what I've done wrong! Trying to rig a Map I'm trying to make a "simple" accordion map in Blender 2.79, for animated and still render purposes.  I will map graphics onto each face, and I don't want the faces to get stretched/distorted.  I do however, want to be able to create a hinge-type rig, to be able to fold open and close the map like an accordion without having to manually position each face edge (which would distort the faces anyways).  I looked into using an Armature, but the faces got distorted. I tried to use a Hinge constraint, but I if understand correctly, it would require each flap of the map to be a distinct element - I don't want that. I found solutions involving Weight painting, but I don't think I want any of the map's flaps to be anchored - also there is only one face per element and I don't know if Weight Painting is appropriate.    How can I rig this map properly to open it and close it without any distortion? I'd like to make links to all files in a directory tree. Which means, create the same directory structure and make the links in them to the respective subdirectory in the original dir.  That could be done with   cp -R -s ../foo .   But - that needs an absolute path. So rather  cp -R -s `readlink -e ../foo` `readlink -e .`   I would like the resulting links to be relative.  How would I do that? I've seen several examples of code like this:  if not someobj:     #do something   But I'm wondering why not doing:  if someobj == None:     #do something   Is there any difference? Does one have an advantage over the other? I just installed a fresh install of 32-bit 12.04 LTS Pangolin today. When I tried to install a few applications, it was really slow. But when I download a .deb or .tar.gz file from on my web browser, it is a lot faster.  Computer specs:  HP Pavilion Slimline s7700n PC  [Memory]         873.7 MiB  [Processor]      AMD Athlon(tm) 64 X2 Dual Core Provessor 3800+ x 2  [Graphics]       GeForce 6105 LE/integrated/SSE2/3DNOW!  [Disk Size] 638.5 GB  I normally get 200-400 kbps.  This is the comparison. I'm running CentOS 7.0 build 1503. I'm trying to search for commands I don't know the name of by searching the man descriptions for multiple keywords using AND (e.g. search for a command containing the both words "create" and "group" in the description).  So I came across the command apropos (which is an alias for man -k). The default behaviour when given multiple keywords is to return any command matching any of the keywords, which isn't what I want. According to the man page the option -a specifies using AND, to return matches only when all words match.  But this isn't what I'm seeing in practice, so I need some help here - e.g. using Centos 7, if I do:  apropos create user   I see a huge list of commands, seemingly matching any command with create or user in the description, as expected. Noting the list includes an entry for the command 'useradd (8) - create a new user...'.  If I do:  apropos -a create user   I only get 2 commands (environ and open). This is what I'm confused by - I would expect it to return the command 'useradd (8) - create a new user', because i can see from the previous search that command does contain those words in the description. Also the 2 returned commands don't obviously seem to be anything about creating users. What am I doing wrong? I'm sure it's something embarrassingly obvious, for that I apologise in advance.  Thanks You can also contact me to customize your template, or create a new unique one.   Do I need to put a comma between the new and unique adjectives in this sentence?  In my native language (if I am not mistaken) we don't put a comma if the adjectives are of a different type. Not sure about English though, and if it's the case here anyway. Any help would be appreciated!