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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(-...
How to remove a key from Hash and get the remaining hash in Ruby/Rails?
...m a hash and get the remaining hash in Ruby.
.slice => It will return selected keys and not delete them from the original hash. Use slice! if you want to remove the keys permanently else use simple slice.
2.2.2 :074 > hash = {"one"=>1, "two"=>2, "three"=>3}
=> {"one"=>1, "tw...
How can I run just the statement my cursor is on in SQL Server Management Studio?
...
Use Ctrl+KU to select a line.
Then use F5 to run it.
Although it only works for single line selection, still I find it quite useful.
Hope it helps!!
share
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What is a method group in C#?
...
Also, if you are using LINQ, you can apparently do something like myList.Select(methodGroup).
So, for example, I have:
private string DoSomethingToMyString(string input)
{
// blah
}
Instead of explicitly stating the variable to be used like this:
public List<string> GetStringStuff()...
PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
...and sequences too. Here's what I did:
Tables:
for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" YOUR_DB` ; do psql -c "alter table \"$tbl\" owner to NEW_OWNER" YOUR_DB ; done
Sequences:
for tbl in `psql -qAt -c "select sequence_name from information_schem...
How to output MySQL query results in CSV format?
...ech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-file/
SELECT order_id,product_name,qty
FROM orders
WHERE foo = 'bar'
INTO OUTFILE '/var/lib/mysql-files/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n';
Using this command columns names will not be e...
How to ignore SVN folders in WinMerge?
...ersion housekeeping directories
d: \\.svn$
d: \\._svn$
Save it, then when selecting items to merge, select the filter you defined from the Select Files or Folders dialog box. Bonus points: It will save this and use it as a default for future merges.
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Change Author template in Android Studio
...ferences dialog.
2)In the search box, write "File and Code Templates".
3)Select the left menu item "File and Code Templates".
4)From the middle tabular navigation section, select Includes.
5)Select File Header item that applies to the Java files.
6)You will find an editor section that allow you...
How to select all instances of selected region in Sublime Text
Is there a shortcut key or single-step menu option to find and select all instances of a highlighted selection in Sublime Text?
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How to load json into my angular.js ng-model?
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<div ng-controller='MikesAngularController'>
<span>Please select a customer:</span>
<select ng-model="selectedCustomer" ng-options="customer.CustomerID as customer.CompanyName for customer in listOfCustomers" style="width:350px;"></select>
</div>
And th...