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List distinct values in a vector in R
...els( data$product_code )
If it's not a factor, but it should be, you can convert it to factor first by using the factor() function, e.g.
levels( factor( data$product_code ) )
Another option, as mentioned above, is the unique() function:
unique( data$product_code )
The main difference between...
Unable to access JSON property with “-” dash
...-CodeSlayer2010: You should use style.boxShadow instead. The style object converts hyphens to camelCase.
– SLaks
Oct 5 '16 at 16:21
...
Creating a byte array from a stream
...e[16*1024];
using (MemoryStream ms = new MemoryStream())
{
int read;
while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
}
return ms.ToArray();
}
}
With .NET 4 and above, I'd use Stream.CopyTo, wh...
Format in kotlin string templates
...at(n) function you'd need to define yourself as
fun Double.format(digits: Int) = "%.${digits}f".format(this)
There's clearly a piece of functionality here that is missing from Kotlin at the moment, we'll fix it.
share
...
Why does range(start, end) not include end?
...btract 1. This also follows the common trend of programmers preferring for(int i = 0; i < 10; i++) over for(int i = 0; i <= 9; i++).
If you are calling range with a start of 1 frequently, you might want to define your own function:
>>> def range1(start, end):
... return range(st...
Get Maven artifact version at runtime
...nfiguration>
</plugin>
Ideally this configuration should be put into the company pom or another base-pom.
Detailed documentation of the <archive> element can be found in the Maven Archive documentation.
sha...
Use LINQ to get items in one List, that are not in another List
... these approaches mandate an O(n*m) operation. That may be fine, but could introduce performance issues, and especially if the data set is quite large. If this doesn't satisfy your performance requirements, you may need to evaluate other options. Since the stated requirement is for a solution in LIN...
Functions that return a function
... return any object from a function. You can return a true/false value. An integer (1,2,3,4...). You can return a string. You can return a complex object with multiple properties. And you can return a function. a function is just a thing.
In your case, returning b returns the thing, the thing...
How do you UrlEncode without using System.Web?
...ne Breaks
All of them listed here (other than HttpUtility.HtmlEncode) will convert "\n\r" into %0a%0d or %0A%0D
Please feel free to edit this and add new characters to my test string, or leave them in the comments and I'll edit it.
...
How to get rid of `deprecated conversion from string constant to ‘char*’` warnings in GCC?
...
Any functions into which you pass string literals "I am a string literal" should use char const * as the type instead of char*.
If you're going to fix something, fix it right.
Explanation:
You can not use string literals to initialise s...