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Python group by
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Python's built-in itertools module actually has a groupby function , but for that the elements to be grouped must first be sorted such that the elements to be grouped are contiguous in the list:
from operator import itemgetter
sortkeyfn = itemgetter(1)
input = [(...
Quickly reading very large tables as dataframes
... MonetDB.R gives you a data type that pretends to be a data frame but is really a MonetDB underneath, increasing performance. Import data with its monetdb.read.csv function. dplyr allows you to work directly with data stored in several types of database.
Storing data in binary formats can also be...
How to read json file into java with simple JSON library
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Well, you want to process all of the items in the array in a loop. My code just gets you the first item (a.get(0)) because that was the closest match to your original code. The json-simple documentation says a JSONArray is java.util.List, so you can...
Ruby on Rails - Import Data from a CSV file
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The smarter_csv gem was specifically created for this use-case: to read data from CSV file and quickly create database entries.
require 'smarter_csv'
options = {}
SmarterCSV.process('input_file.csv', options) do |chunk|
chunk.each do |data_hash|
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Site stopped working in asp.net System.Web.WebPages.Razor.Configuration.HostSection cannot be cast t
...), updated the web.config file accordingly and it still didn't work.
It finally worked when i changed my web.config file (INSIDE THE VIEWS directory) from:
<sectionGroup name="system.web.webPages.razor" type="System.Web.WebPages.Razor.Configuration.RazorWebSectionGroup, System.Web.WebPages.Razor...
Is there a read-only generic dictionary available in .NET?
...lt;TKey, TValue>
{
private readonly IDictionary<TKey, TValue> _dictionary;
public ReadOnlyDictionary()
{
_dictionary = new Dictionary<TKey, TValue>();
}
public ReadOnlyDictionary(IDictionary<TKey, TValue> dictionary)
{
_dictionary = dict...
Can Objective-C switch on NSString?
... @abbood For more information about enum, see the posting NS_ENUM & NS_OPTIONS by Mattt Thompson.
– Basil Bourque
Oct 21 '13 at 21:32
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Add column with constant value to pandas dataframe [duplicate]
...ods to gain some intuition for alignment works with objects that have partially, totally, and not-aligned-all aligned indices. For example here's how DataFrame.align() works with partially aligned indices:
In [7]: from pandas import DataFrame
In [8]: from numpy.random import randint
In [9]: df = ...
Simple way to encode a string according to a password?
... to do much work to implement a proper encryption scheme however. First of all, don’t re-invent the cryptography wheel, use a trusted cryptography library to handle this for you. For Python 3, that trusted library is cryptography.
I also recommend that encryption and decryption applies to bytes; ...
ASP.NET MVC 3: Override “name” attribute with TextBoxFor
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Rob, actually there is a much simpler way. Instead of name, use Name:
@Html.TextBoxFor(x => x.Data, new { Name = Model.Key + "_Data", id = Model.Key + "_Data" })
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