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Assigning a variable NaN in python without numpy
...r all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation on NaN value may cause subtle issues when trying to store NaN inside con...
How to watch for array changes?
...-based assignment? I want something that would fire an event that I could handle.
10 Answers
...
What do the return values of node.js process.memoryUsage() stand for?
...
In order to answer this question, one has to understand V8’s Memory Scheme first.
A running program is always represented through some space allocated in memory. This space is called Resident Set. V8 uses a scheme similar to the Java Virtual Machine and divides the memory i...
How do I check if a number evaluates to infinity?
...lert(x === Infinity); displays "true". (Admittedly that's an obscure case, and anyone who decides to redefine Infinity, NaN etc should expect odd things to happen.)
– LukeH
Jan 18 '11 at 13:49
...
How to center a button within a div?
...r, however Flexbox would be the correct approach now.
Live Demo
Vertical and horizontal alignment.
#wrapper {
display: flex;
align-items: center;
justify-content: center;
}
Just horizontal (as long as the main flex axis is horizontal which is default)
#wrapper {
display: flex;
justif...
Comparison of Lucene Analyzers
...ifferent analyzers within Lucene? I am getting a maxClauseCount exception and I understand that I can avoid this by using a KeywordAnalyzer but I don't want to change from the StandardAnalyzer without understanding the issues surrounding analyzers. Thanks very much.
...
How to iterate over the keys and values in an object in CoffeeScript?
...ld not initialise arr as arr = [], you should use arr = {}. In Javascript (and Coffeescript) arrays have numeric indices. Objects behave like associative arrays/dicts.
– Morgan Harris
Mar 18 '13 at 3:55
...
How to implement WiX installer upgrade?
...omatic upgrades. It prevents downgrades, giving a localised error message, and also prevents upgrading an already existing identical version (i.e. only lower versions are upgraded):
<MajorUpgrade
AllowDowngrades="no" DowngradeErrorMessage="!(loc.NewerVersionInstalled)"
AllowSameVersionUp...
iPad browser WIDTH & HEIGHT standard
Does anyone know the safest width and height for the BODY when viewing any web page on the iPad? I want to avoid the scrollbars as much as possible.
...
Ruby, Difference between exec, system and %x() or Backticks
...tem
The system method calls a system program. You have to provide the command as a string argument to this method. For example:
>> system("date")
Wed Sep 4 22:03:44 CEST 2013
=> true
The invoked program will use the current STDIN, STDOUT and STDERR objects of your Ruby program. In fact...