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What is the most efficient way to loop through dataframes with pandas? [duplicate]
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Pandas is based on NumPy arrays.
The key to speed with NumPy arrays is to perform your operations on the whole array at once, never row-by-row or item-by-item.
For example, if close is a 1-d array, and you want the day-over-day percent change,
pct_...
Find size of an array in Perl
I seem to have come across several different ways to find the size of an array. What is the difference between these three methods?
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Cannot deserialize the JSON array (e.g. [1,2,3]) into type ' ' because type requires JSON object (e.
... string is wrapped within square brackets ([]), hence it is interpreted as array instead of single RetrieveMultipleResponse object. Therefore, you need to deserialize it to type collection of RetrieveMultipleResponse, for example :
var objResponse1 =
JsonConvert.DeserializeObject<List<Re...
What is the difference between ndarray and array in numpy?
What is the difference between ndarray and array in Numpy? And where can I find the implementations in the numpy source code?
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What are the differences between Generics in C# and Java… and Templates in C++? [closed]
...1.1 code to C# 2.0
Java Generics allow you to declare something like this.
ArrayList<Person> foo = new ArrayList<Person>();
On the surface it looks the same, and it sort-of is. The compiler will also prevent you from putting things that aren't Person into the list.
The difference is wha...
Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;
Since updating to ADT 14 I can no longer build my project. It was building fine prior to updating.
54 Answers
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Only get hash value using md5sum (without filename)
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A simple array assignment works... Note that the first element of a bash array can be addressed by just the name without the [0] index, ie, $md5 contains only the 32 chars of the md5sum.
md5=($(md5sum file))
echo $md5
# 53c8fdfcbb...
How to use php serialize() and unserialize()
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A PHP array or object or other complex data structure cannot be transported or stored or otherwise used outside of a running PHP script. If you want to persist such a complex data structure beyond a single run of a script, you need...
Getting an object from an NSSet
...embership, use anyObject to get a member (not random), or convert it to an array (in no particular order) with allObjects.
A set is appropriate when you don't want duplicates, don't care about order, and want fast membership testing.
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How can I add an item to a IEnumerable collection?
... that:
items = items.Concat(new[] { "foo" });
This will not change the array object (you cannot insert items into to arrays, anyway). But it will create a new object that will list all items in the array, and then "Foo". Furthermore, that new object will keep track of changes in the array (i.e. ...