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Finding the average of a list
...tistics.mean(l) # 20.11111111111111
On older versions of Python you can do
sum(l) / len(l)
On Python 2 you need to convert len to a float to get float division
sum(l) / float(len(l))
There is no need to use reduce. It is much slower and was removed in Python 3.
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convert a list of objects from one type to another using lambda expression
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Is there a way to do this without having a concrete implementation for TargetType? I've ended up with something like this: List<ISearchEntity> results = myIQueryable.Select(x => (ISearchEntity) new TargetType { MyField = "Field value ...
How to make completely transparent navigation bar in iOS 7
... I could find makes it translucent but not transparent. I know this can be done in iOS 7 because it is used in the notes app. My question is, what is the code they used to do it?
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How to watch for array changes?
...g you to intercept method calls, accessors, etc. Most importantly, you can do this without even providing an explicit property name... which would allow you to test for an arbitrary, index-based access/assignment. You can even intercept property deletion. Proxies would effectively allow you to inspe...
How to remove duplicate white spaces in string using Java?
...replaceAll("\\s+", " ");
For example
System.out.println("lorem ipsum dolor \n sit.".replaceAll("\\s+", " "));
outputs
lorem ipsum dolor sit.
What does that \s+ mean?
\s+ is a regular expression. \s matches a space, tab, new line, carriage return, form feed or vertical tab, and + says "...
Regular Expression to find a string included between two characters while EXCLUDING the delimiters
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Easy done:
(?<=\[)(.*?)(?=\])
Technically that's using lookaheads and lookbehinds. See Lookahead and Lookbehind Zero-Width Assertions. The pattern consists of:
is preceded by a [ that is not captured (lookbehind);
a non-gr...
QString to char* conversion
...ying to convert a QString to char* type by the following methods, but they don't seem to work.
10 Answers
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javac error: Class names are only accepted if annotation processing is explicitly requested
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I would agree. Especially since it is an easy mistake to do (since the .class should be omitted when launching with java).
– aioobe
Feb 21 '11 at 7:26
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Add border-bottom to table row
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I had a problem like this before. I don't think tr can take a border styling directly. My workaround was to style the tds in the row:
<tr class="border_bottom">
CSS:
tr.border_bottom td {
border-bottom: 1px solid black;
}
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How can I use redis with Django?
I've heard of redis-cache but how exactly does it work? Is it used as a layer between django and my rdbms, by caching the rdbms queries somehow?
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