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Filter rows which contain a certain string
...mail in the comments above. You can use regular expressions for the second and subsequent arguments of filter like this:
dplyr::filter(df, !grepl("RTB",TrackingPixel))
Since you have not provided the original data, I will add a toy example using the mtcars data set. Imagine you are only intereste...
How to fix “Headers already sent” error in PHP
...ically
Previous error messages or notices
Intentional:
print, echo and other functions producing output
Raw <html> sections prior <?php code.
Why does it happen?
To understand why headers must be sent before output it's necessary
to look at a typical HTTP
response. PHP scripts ...
RSA Public Key format
...ers from ---- BEGIN SSH2 PUBLIC KEY ---- to -----BEGIN RSA PUBLIC KEY----- and expect that it will be sufficient to convert from one format to another (which is what you've done in your example).
This article has a good explanation about both formats.
What you get in an RSA PUBLIC KEY is closer to...
Why do we copy then move?
I saw code somewhere in which someone decided to copy an object and subsequently move it to a data member of a class. This left me in confusion in that I thought the whole point of moving was to avoid copying. Here is the example:
...
Why do we need RESTful Web Services?
...ed if it is very important for you to minimize the coupling between client and server components in a distributed application.
This may be the case if your server is going to be used by many different clients that you do not have control over. It may also be the case if you want to be able to upda...
Multi-key dictionary in c#? [duplicate]
...<T1,T2>(item1, item2);
}
}
You get immutability, .GetHashcode and .Equals for free, which (while you're waiting for C# 4.0) is nice 'n simple...
One warning however: the default GetHashcode implementation (sometimes) only considers the first field so make sure to make the first field t...
How do you use version control with Access development?
...t has a good amount of VBA, a number of queries, a small amount of tables, and a few forms for data entry & report generation. It's an ideal candidate for Access.
...
What Haskell representation is recommended for 2D, unboxed pixel arrays with millions of pixels?
...ge-processing problems in Haskell. I'm working with both bitonal (bitmap) and color images with millions of pixels. I have a number of questions:
...
What are some compelling use cases for dependent method types?
...perimental feature before, has now been enabled by default in the trunk , and apparently this seems to have created some excitement in the Scala community.
...
When should I mock?
I have a basic understanding of mock and fake objects, but I'm not sure I have a feeling about when/where to use mocking - especially as it would apply to this scenario here .
...