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dplyr: “Error in n(): function should not be called directly”
...ction" specification, like example below:
delay <- dplyr::summarise(by_tailnum,
count = n(),
dist = mean(distance, na.rm = TRUE),
delay = mean(arr_delay, na.rm = TRUE))
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Bash if statement with multiple conditions throws an error
...ions.
tldp.org/LDP/Bash-Beginners-Guide/html/sect_07_01.html
Update
Actually you could still use && and || with the -eq operation. So your script would be like this:
my_error_flag=1
my_error_flag_o=1
if [ $my_error_flag -eq 1 ] || [ $my_error_flag_o -eq 2 ] || ([ $my_error_flag -eq 1 ] ...
What does each of the [y,n,q,a,d,/,K,j,J,g,e,?] stand for in context of git -p
...this hunk nor any of the remaining ones
a - stage this hunk and all later hunks in the file
d - do not stage this hunk nor any of the later hunks in the file
g - select a hunk to go to
/ - search for a hunk matching the given regex
j - leave thi...
How to create SBT project with IntelliJ Idea?
...Sbt developing, and I'd like to import a Sbt project in IntelliJ Idea.
Actually, I managed to import my project in two different ways:
...
How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
...
linq where list contains any in list
...
Sounds like you want:
var movies = _db.Movies.Where(p => p.Genres.Intersect(listOfGenres).Any());
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fo...
Finding the type of an object in C++
...
dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime...
Firefox Add-on RESTclient - How to input POST parameters?
... to do this? Or is there any other tool which can be used to debug an REST API on Mac OS X ?
5 Answers
...
How to convert a number to string and vice versa in C++
...o-number conversion and vice-versa are built in into the standard library. All the following functions are present in <string> (as per paragraph 21.5).
string to numeric
float stof(const string& str, size_t *idx = 0);
double stod(const string& str, size_t *id...
Tomcat: How to find out running tomcat version
....in/blog/check-jsp-tomcat-version
Save this code into a file called tomcat_version.jsp:
Tomcat Version : <%= application.getServerInfo() %><br>
Servlet Specification Version :
<%= application.getMajorVersion() %>.<%= application.getMinorVersion() %> <br> ...