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Order data frame rows according to vector with specific order
...work as long as your target contains exactly the same elements as df$name, and neither contain duplicate values.
From ?match:
match returns a vector of the positions of (first) matches of its first argument
in its second.
Therefore match finds the row numbers that matches target's elements, and...
How to do multiple arguments to map function where one remains the same in python?
...ally is an issue for you, the speed difference between list comprehensions and map() won't help either way.
– Sven Marnach
May 31 '12 at 13:54
...
String.Join method that ignores empty strings?
... I'm getting an error: "'Where' is not a member of 'System.Array'". And I don't see anything about 'Where' on MSDN: msdn.microsoft.com/en-us/library/system.array.aspx
– Doug
May 2 '13 at 12:55
...
Comparing two CGRects
... postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9....
What does @@variable mean in Ruby?
What are Ruby variables preceded with double at signs ( @@ )? My understanding of a variable preceded with an at sign is that it is an instance variable, like this in PHP:
...
Operator overloading : member function vs. non-member function?
... as member function is asymmetric because it can have only one parameter and the other parameter passed automatically is the this pointer. So no standard exists to compare them. On the other hand, overloaded operator declared as a friend is symmetric because we pass two arguments of the same...
Sorting list based on values from another list?
...t should be: The list is ordered regarding the first element of the pairs, and the comprehension extracts the 'second' element of the pairs.
– MasterControlProgram
Oct 6 '17 at 14:31
...
Why would one use nested classes in C++?
Can someone please point me towards some nice resources for understanding and using nested classes? I have some material like Programming Principles and things like this IBM Knowledge Center - Nested Classes
...
How to override equals method in Java
... in Java. I have a class People which basically has 2 data fields name and age . Now I want to override equals method so that I can check between 2 People objects.
...
Fill remaining vertical space with CSS using display:flex
...tomato;
/* no flex rules, it will grow */
}
div {
flex: 1; /* 1 and it will fill whole space left if no flex value are set to other children*/
background: gold;
overflow: auto;
}
footer {
background: lightgreen;
min-height: 60px; /* min-height has its purpose :) , unless ...