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Repeat each row of data.frame the number of times specified in a column
...es
library(dplyr)
df %>%
slice(rep(seq_len(n()), freq)) %>%
select(-freq)
# var1 var2
#1 a d
#2 b e
#3 b e
#4 c f
#5 c f
#6 c f
seq_len(n()) part can be replaced with any of the following.
df %>% slice(rep(1:nrow(df), freq)) %>% select(-...
Edit changeset comment after updates have been checked in to TFS
...u know a specific file that was included in the changeset then find it and select it (can be done from the Solution Explorer panel)
right click, select View History (Source Explorer) or Source Control -> View History (Solution Explorer)
find the specific change you are interested in, then ri...
Use LINQ to get items in one List, that are not in another List
...erride the equality:
var excludedIDs = new HashSet<int>(peopleList1.Select(p => p.ID));
var result = peopleList2.Where(p => !excludedIDs.Contains(p.ID));
This variant does not remove duplicates.
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MySQL convert date string to Unix timestamp
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Here's an example of how to convert DATETIME to UNIX timestamp:
SELECT UNIX_TIMESTAMP(STR_TO_DATE('Apr 15 2012 12:00AM', '%M %d %Y %h:%i%p'))
Here's an example of how to change date format:
SELECT FROM_UNIXTIME(UNIX_TIMESTAMP(STR_TO_DATE('Apr 15 2012 12:00AM', '%M %d %Y %h:%i%p')),'%m-%d-...
Can't install PIL after Mac OS X 10.9
...ution below, provided by Will.
open your terminal and execute:
xcode-select --install
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Convert a list of objects to an array of one of the object's properties
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You are looking for
MyList.Select(x=>x.Name).ToArray();
Since Select is an Extension method make sure to add that namespace by adding a
using System.Linq
to your file - then it will show up with Intellisense.
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jQuery Selector: Id Ends With?
Is there a selector that I can query for elements with an ID that ends with a given string?
9 Answers
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C# - Selectively suppress custom Obsolete warnings
... },
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true,enableSnippets:true
});
}
});
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Count the occurrences of DISTINCT values
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SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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Multi-statement Table Valued Function vs Inline Table Valued Function
...statement table valued function (MSTVF) even if they both simply execute a SELECT statement. SQL Server will treat an ITVF somewhat like a VIEW in that it will calculate an execution plan using the latest statistics on the tables in question. A MSTVF is equivalent to stuffing the entire contents of ...