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To find whether a column exists in data frame or not
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Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
share
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How to create own dynamic type or dynamic object in C#?
There, is for example, ViewBag property of ControllerBase class and we can dynamically get/set values and add any number of additional fields or properties to this object, which is cool .I want to use something like that, beyond MVC application and Controller class in other types of applicatio...
Connection string using Windows Authentication
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Replace the username and password with Integrated Security=SSPI;
So the connection string should be
<connectionStrings>
<add name="NorthwindContex"
connectionString="data source=localhost;
initial catalog=northwind;persist sec...
How do I access the request object or any other variable in a form's clean() method?
...gument, request. This stores the request in the form, where it's required, and from where you can access it in your clean method.
class MyForm(forms.Form):
def __init__(self, *args, **kwargs):
self.request = kwargs.pop('request', None)
super(MyForm, self).__init__(*args, **kwar...
What is difference between width, innerWidth and outerWidth, height, innerHeight and outerHeight in
... to see what is the difference, but they display me same results for width and height.
6 Answers
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How to specify Composer install path?
... is there a way to specify the vendor dir for some specific package only, and leave the others as default?
– mr1031011
Dec 24 '12 at 9:08
1
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Mercurial .hgignore for Visual Studio 2010 projects
...re asking about an entry that's already there.. Feel free to edit the list and yes I totally agree, it should be added
– Shady M. Najib
Apr 14 '11 at 12:07
2
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How to get a json string from url?
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If you're using .NET 4.5 and want to use async then you can use HttpClient in System.Net.Http:
using (var httpClient = new HttpClient())
{
var json = await httpClient.GetStringAsync("url");
// Now parse with JSON.Net
}
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Hyphen, underscore, or camelCase as word delimiter in URIs?
...ed API for an intranet app. I realize it's a pretty small concern in the grand scheme of things, but: should I use hyphens, underscores, or camelCase to delimit words in the URIs?
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How to compare two dates?
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Use the datetime method and the operator < and its kin.
>>> from datetime import datetime, timedelta
>>> past = datetime.now() - timedelta(days=1)
>>> present = datetime.now()
>>> past < present
True
>&g...