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ggplot2 plot without axes, legends, etc
...at, aes(x=x, y=y)) +
geom_point() +
scale_x_continuous(expand=c(0,0)) +
scale_y_continuous(expand=c(0,0))
p + theme(axis.line=element_blank(),axis.text.x=element_blank(),
axis.text.y=element_blank(),axis.ticks=element_blank(),
axis.title.x=element_bl...
What is the difference between new/delete and malloc/free?
What is the difference between new / delete and malloc / free ?
15 Answers
15
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What does “hashable” mean in Python?
...ue which never changes during its lifetime (it needs a __hash__() method), and can be compared to other objects (it needs an __eq__() or __cmp__() method). Hashable objects which compare equal must have the same hash value.
Hashability makes an object usable as a dictionary key and a set member...
How to configure PostgreSQL to accept all incoming connections
...of IPs to be authorized, you could edit /var/lib/pgsql/{VERSION}/data file and put something like
host all all 172.0.0.0/8 trust
It will accept incoming connections from any host of the above range.
Source: http://www.linuxtopia.org/online_books/database_guides/P...
Can I install Python 3.x and 2.x on the same Windows computer?
I'm running Windows and the shell/OS automatically runs Python based on the registry settings when you run a program on the command line. Will this break if I install a 2.x and 3.x version of Python on the same machine?
...
How to report an error from a SQL Server user-defined function
...lect, this alone doesn't work because nothing is returned - not even null, and in my case I wanted to throw an error when nothing was found. I didn't want to break down the inline function into a multi-statment one for obvious performance reasons. Instead I used your solution plus ISNULL and MAX. ...
How do I add more members to my ENUM-type column in MySQL?
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Most ALTER TABLE commands will completely rewrite the whole table. Is mysql clever enough to not do that with enum ?
– John
Oct 9 '18 at 22:10
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When should I use a struct instead of a class?
...
MSDN has the answer:
Choosing Between Classes and Structures.
Basically, that page gives you a 4-item checklist and says to use a class unless your type meets all of the criteria.
Do not define a structure unless the
type has all of the following
characterist...
Debug a java application without starting the JVM with debug arguments
...ny experiences to share with this?
– Thorbjørn Ravn Andersen
Jul 15 '12 at 16:52
1
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Postgresql: Conditionally unique constraint
...le slower, the advantage of the exclude solution is that it is deferrable (and by default defers until the end of the statement). In contrast, the accepted unique index solution cannot be deferred (and is checked after every row change). So a bulk update is often not possible because steps during th...