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How can I count the occurrences of a list item?
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Use Counter if you are using Python 2.7 or 3.x and you want the number of occurrences for each element:
>>> from collections import Counter
>>> z = ['blue', 'red', 'blue', 'yellow', 'blue', 'red']
>>> Counter(z)
Counter({'blue': 3, 'red': 2, 'ye...
Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
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Turning live() into on() in jQuery
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The on documentation states (in bold ;)):
Event handlers are bound only to the currently selected elements; they must exist on the page at the time your code makes the call to .on().
Equivalent to .live() would be something like
$(document.body).on('change', 'select[nam...
How is null + true a string?
...where op is an overloadable binary operator, x is an expression of type X, and y is an expression of type Y, is processed as follows:
The set of candidate user-defined operators provided by X and Y for the operation operator op(x, y) is determined. The set consists of the union of the candid...
How default .equals and .hashCode will work for my classes?
...t's (generally speaking; if you inherit from a class that redefined equals and/or hashCode, then you'll use that implementation instead).
From the documentation:
equals
The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, f...
How do I Moq a method that has an optional argument in its signature without explicitly specifying i
...e changes the default value of b to true? This will lead to failing tests (and rightfully so), but they will be more difficult to fix because of the hidden assumption that b is false. Explicitly specifying the bool parameter has another benefit: it improves the readability of your tests. Someone goi...
Php multiple delimiters in explode
I have a problem, I have a string array, and I want to explode in different delimiter. For Example
12 Answers
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Choice between vector::resize() and vector::reserve()
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The two functions do vastly different things!
The resize() method (and passing argument to constructor is equivalent to that) will insert or delete appropriate number of elements to the vector to make it given size (it has optional second argument to specify their value). It will affect the ...
Installing Ruby Gem in Windows
...ckage management system of your
distribution or third-party tools (rbenv and RVM).
On OS X machines, you can use third-party tools (rbenv and RVM).
On Windows machines, you can use RubyInstaller.
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Javascript : Send JSON Object with Ajax?
...HttpRequest(); // new HttpRequest instance
xmlhttp.open("POST", "/json-handler");
xmlhttp.setRequestHeader("Content-Type", "application/json");
xmlhttp.send(JSON.stringify({name:"John Rambo", time:"2pm"}));
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