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Cleaning `Inf` values from an R dataframe
...,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)
invisible(lapply(names(DT),function(.name) set(DT, which(is.infinite(DT[[.name]])), j = .name,value =NA)))
Or using colum...
How to force a line break in a long word in a DIV?
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For this to work in a table, you may need to apply the table-layout: fixed; to the table
– Serj Sagan
Jan 23 '14 at 23:27
30
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Centering a div block without the width
...on and don't have the luxury of having a good one to choose. A single-cell table is another option, although a table with one cell isn't really a table, is it?
– Mike M. Lin
Jan 9 '13 at 18:03
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Android Studio quick documentation always “fetching documentation”
...ven when the documentation is already downloaded.
The default link in jdk.table.xml is http://developer.android.com/reference/ (android studio tries to connect to this online server even if the network is blocked).
To solve the problem, we can just redirect the reference to local source.
MacOS
O...
Foreign key constraint may cause cycles or multiple cascade paths?
I have a problem when I try to add constraints to my tables. I get the error:
9 Answers
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B-Tree vs Hash Table
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You can only access elements by their primary key in a hashtable.
This is faster than with a tree algorithm (O(1) instead of log(n)), but you cannot select ranges (everything in between x and y).
Tree algorithms support this in Log(n) whereas hash indexes can result in a full table s...
How to sum a variable by group
...he syntax behind each alternative. For instance, if I have a larger source table and want to subselect just two dimensions plus summed metrics, can I adapt any of these methods? Hard to tell.
– Dodecaphone
Oct 28 '18 at 10:42
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What are the use cases for selecting CHAR over VARCHAR in SQL?
... Another reason is page splits and fragmentation. I had a table with an IDEN PK that got 99% fragmented because of page splits on varchar columns. A very active table and by nature of the application a new row empty row would get created and then populated. Char fixed the fragme...
What is DOM Event delegation?
...efinition.
It refers to handling bubbling events from many elements, like table cells, from a parent object, like the table. It can keep the code simpler, especially when adding or removing elements, and saves some memory.
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What is a stored procedure?
...ut the user will not need to have read/write permissions on the underlying tables. This is a good first step against SQL injection.
Stored procedures do come with downsides, basically the maintenance associated with your basic CRUD operation. Let's say for each table you have an Insert, Update, Del...