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Repeat each row of data.frame the number of times specified in a column
...q(nrow(df)), df$freq), 1:2]
The code for data.table is a tad cleaner:
# convert to data.table by reference
setDT(df)
df.expanded <- df[rep(seq(.N), freq), !"freq"]
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Select rows of a matrix that meet a condition
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This is easier to do if you convert your matrix to a data frame using as.data.frame(). In that case the previous answers (using subset or m$three) will work, otherwise they will not.
To perform the operation on a matrix, you can define a column by nam...
How to elegantly deal with timezones
...he client knows what timezone it is in, so it can with reasonable accuracy convert times into UTC.
When rendering views, they were using the HTML5 <time> element, they would never render datetimes directly in the ViewModel. It was implemented as as HtmlHelper extension, something like Html.Ti...
Frequency table for a single variable
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Is there an easy way to convert these counts to proportions?
– dsaxton
Jul 31 '15 at 23:53
7
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Convert hex color value ( #ffffff ) to integer value
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Answer is really simple guys, in android if you want to convert hex color in to int, just use android Color class, example shown as below
this is for light gray color
Color.parseColor("#a8a8a8");
Thats it and you will get your result.
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How can I convert spaces to tabs in Vim or Linux?
I've looked over several questions on Stack Overflow for how to convert spaces to tabs without finding what I need. There seem to be more questions about how to convert tabs to spaces, but I'm trying to do the opposite.
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Convert .pfx to .cer
Is it possible to convert a .pfx (Personal Information Exchange) file to a .cer (Security Certificate) file? Unless I'm mistaken, isn't a .cer somehow embedded inside a .pfx? I'd like some way to extract it, if possible.
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How to print VARCHAR(MAX) using Print Statement?
... This works for me on SQL 2008 R2 SP2 (10.50.1600) using either CAST() or CONVERT(), and on SQL 2008 SP2 (10.0.5500).
– user593806
Nov 5 '13 at 10:13
26
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Downloading a Google font and setting up an offline site that uses it
...u downloaded (.ttf should be extracted)
Go to "http://ttf2woff.com/" and convert any .ttf extracted from zip to .woff
Edit desiredfontname.css and replace any url within it [between 'url(' and ')'] with the corresponding converted .woff file you got on ttf2woff.com; path you write should be acco...
How to do a FULL OUTER JOIN in MySQL?
... syntax. According to MySql's outer join simplification, the right join is converted to the equivalent left join by switching the t1 and t2 in the FROM and ON clause in the query. Thus, the MySql Query Optimizer translates the original query into the following -
SELECT * FROM t1
LEFT JOIN t2 ON t1...