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How to select the row with the maximum value in each group
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Here's a data.table solution:
require(data.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
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How can I rename a field for all documents in MongoDB?
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For some reason, this didn't work for me when I used the "table.field" : "table.field" syntax. It did work when I just used the "field" : "field" syntax.
– Ben
Sep 2 '15 at 0:21
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Can I create a named default constraint in an add column statement in SQL Server?
In SQL Server, I have a new column on a table:
4 Answers
4
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Rails 4: List of available datatypes
... is not set to use :sql, then your schema.rb file wont be able to dump the table that uses types like :json. The schema will still be dumped for the tables that use default types but you'll see a comment for the table with special types like, "could not dump table...". Look here to set the schema_fo...
Is it possible to refresh a single UITableViewCell in a UITableView?
I have a custom UITableView using UITableViewCell s.
Each UITableViewCell has 2 buttons. Clicking these buttons will change an image in a UIImageView within the cell.
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How to remove an element slowly with jQuery?
...otstrap.min.css" rel="stylesheet"/>
</head>
<body>
<table class="table table-striped table-bordered table-hover">
<thead>
<tr>
<th>id</th>
<th>firstname</th>
<th>lastname</th>
<th&g...
What's the recommended approach to resetting migration history using Django South?
...ion and fake-applies it (since your database already has the corresponding tables). There's no need to drop all the app tables during the process.
Here's what I'm doing on my dev + production server when I need to get rid of all these unneeded dev migrations:
Make sure we have the same DB sche...
How should a model be structured in MVC? [closed]
...n Object-Relational Mapping technique (ORM) nor an abstraction of database tables. Anyone who tells you otherwise is most likely trying to 'sell' another brand-new ORM or a whole framework.
What a model is:
In proper MVC adaptation, the M contains all the domain business logic and the Model Layer ...
What is the best way to insert source code examples into a Microsoft Word document?
... I initially used the same technique but have since changed to using a table of 1x1 because I found that text boxes are an f'ing pain to position. I tried "top and bottom" so the text would be only before and after, and Word would magically move the box up or down, sometimes the caption would no...
MYSQL Dump only certain rows
...t dumps everything. How can I get mysqldump to only dump certain rows of a table?
3 Answers
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