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Count number of rows within each group
..., there is no need to rename each variable in by= like list(year=df1$year) etc. A data.frame is a list already so aggregate(df1[c("Count")], by=df1[c("Year", "Month")], FUN=sum, na.rm=TRUE) will work.
– thelatemail
Jul 17 '19 at 22:27
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Unable to start debugging because the object invoked has disconnected from its clients
...ent processes: devenv, mspdbsrv, vcpkgsrv, msbuild, msvsmon, vshub, vstest etc
Remove .suo, .ncb, .VC.db, .VC.VC.opendb files of the solution as well as .vs directory, which sometimes cause problems
Remove project setting files, sort of YourProjectName.vcproj.DOMAINNAME.LOGINNAME.user or YourProject...
OnCreateOptionsMenu() not called in Fragment
...because I'm using Kotlin and many times you don't have to do findViewById, etc... to get the view you need.
– DWndrer
Sep 16 '18 at 2:54
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Is volatile expensive?
...functions providing additional functionality like getAndSet, compareAndSet etc., so from a performance point of view using it is just useful if you need the added functionality. But I wonder why you refer to the OS here? The functionality is implemented in CPU opcodes directly. And does this imply t...
In C#, What is a monad?
...en be completely oblivious to things like
back-tracking, parser failures etc., and just combine smaller parsers
together as if things would never go wrong, safe in the knowledge that
a clever implementation of Bind sorts out all the logic behind the
difficult bits. Then later on maybe someon...
Get selected text from a drop-down list (select box) using jQuery
...n based on the index of where they occur in the current level of the tree, etc)
– freefaller
Mar 9 '17 at 14:03
Hi how...
How to get first character of string?
...At(0) returns "\ud83d", "café".charAt(3) returns e and drops the accent, etc. stackoverflow.com/questions/38345372/… has some info and a good alternative (use a library)
– Clément
May 30 at 7:32
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Ways to save Backbone.js model data?
... update a resource, (e.g. Change the flavor of lemon donut to limon donut, etc.) you use a PUT request. When you want to delete that model from the server all together, you use a DELETE request.
These basics are very important because with your RESTful app, you probably will have a URI designation ...
How to get the type of a variable in MATLAB?
... want to be even more specific, you can use ischar(), isfloat(), iscell(), etc.
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Python setup.py develop vs install
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not sure if this matters, but if I am using python 3 etc, does one have to run python setup.py develop differently?
– Charlie Parker
Jan 11 '17 at 1:03
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