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Split column at delimiter in data frame [duplicate]
...me.
I added a "x|y" line to avoid ambiguities:
df <- data.frame(ID=11:13, FOO=c('a|b','b|c','x|y'))
foo <- data.frame(do.call('rbind', strsplit(as.character(df$FOO),'|',fixed=TRUE)))
Or, if you want to replace the columns in the existing data.frame:
within(df, FOO<-data.frame(do.call('r...
NULL values inside NOT IN clause
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Query A is the same as:
select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <> null is UNKNOWN,...
What are the aspect ratios for all Android phone and tablet devices?
...═════════════════╣
║ 5 x 3 ║ 0.6 ║ 1.667... ║
╠══════════════════════════╬════════════════════════...
How to compare two floating point numbers in Bash?
...s in scientific format, provided a capital letter E is employed, e.g. num1=3.44E6
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Extract subset of key-value pairs from Python dictionary object?
...t that has several key value pairs (about 16), but I am only interested in 3 of them. What is the best way (shortest/efficient/most elegant) to achieve that?
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Cannot change version of project facet Dynamic Web Module to 3.0?
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WARN Could not determine content-length of response body. Set content-length of the response or set
I just upgraded to rails 3.2.2, and now on rails s, page load, I get all these errors in the log:
3 Answers
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Simple way to calculate median with MySQL
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37 Answers
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How to escape braces (curly brackets) in a format string in .NET
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For you to output foo {1, 2, 3} you have to do something like:
string t = "1, 2, 3";
string v = String.Format(" foo {{{0}}}", t);
To output a { you use {{ and to output a } you use }}.
or Now, you can also use c# string interpolation like this (featu...
Adding a new array element to a JSON object
...eamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}';
var obj = JSON.parse(jsonStr);
obj['theTeam'].push({"teamId":"4","status":"pending"});
jsonStr = JSON.stringify(obj);
// "{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member...