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How can I check for NaN values?
...did not work reliably. Used numpy instead." Having said that, I've not actually ever seen it fail.
– mavnn
Jan 26 '10 at 13:18
24
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Docker build “Could not resolve 'archive.ubuntu.com'” apt-get fails to install anything
... 8.8.8.8
Address 1: 8.8.8.8
If the command appears to hang, but eventually spits out the error "can't resolve 'google.com'", then you have the same problem as me.
The nslookup command queries the DNS server 8.8.8.8 in order to turn the text address of 'google.com' into an IP address. Ironicall...
How to get a Docker container's IP address from the host
...n. Maybe provide two examples clearly labelled Linux and Windows. I literally just typed the example, checked the docs which also uses single quotes and then Googled the error. I'm sure I'm not alone.
– Wyck
Apr 15 '19 at 18:42
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PHP session lost after redirect
...
First, carry out these usual checks:
Make sure session_start(); is called before any sessions are being called. So a safe bet would be to put it at the beginning of your page, immediately after the opening <?php declaration before anything else. Also ensure there are no whitespaces/tabs be...
Private virtual method in C++
...d, without further exposing the virtual functions directly by making them callable by derived classes (as would be possible if the functions were just protected). The point is that virtual functions exist to allow customization; unless they also need to be invoked directly from within derived classe...
How different is Objective-C from C++? [closed]
...
Short list of some of the major differences:
C++ allows multiple inheritance, Objective-C doesn't.
Unlike C++, Objective-C allows method parameters to be named and the method signature includes only the names and types of the parameters and return type (see bbum's and Chuck...
Python Infinity - Any caveats?
...involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440737...
How to know if other threads have finished?
...Thread to complete, or
Check Thread.isAlive() in a polling fashion -- generally discouraged -- to wait until each Thread has completed, or
Unorthodox, for each Thread in question, call setUncaughtExceptionHandler to call a method in your object, and program each Thread to throw an uncaught Exception...
How do I write a bash script to restart a process if it dies?
...crashing on your hands. The sleep 1 takes away the strain from that.
Now all you need to do is start this bash script (asynchronously, probably), and it will monitor myserver and restart it as necessary. If you want to start the monitor on boot (making the server "survive" reboots), you can sched...
Where is the documentation for the values() method of Enum?
...places :
Enum Types, from The Java Tutorials
The compiler automatically adds some special methods when it creates
an enum. For example, they have a static values method that returns an
array containing all of the values of the enum in the order they are
declared. This method is commonl...