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How to plot two histograms together in R?
... new column in each that will be
# a variable to identify where they came from later.
carrots$veg <- 'carrot'
cukes$veg <- 'cuke'
# and combine into your new data frame vegLengths
vegLengths <- rbind(carrots, cukes)
After that, which is unnecessary if your data is in long format already...
Create the perfect JPA entity [closed]
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I'll try to answer several key points: this is from long Hibernate/ persistence experience including several major applications.
Entity Class: implement Serializable?
Keys needs to implement Serializable. Stuff that's going to go in the HttpSession, or be sent over the ...
A fast method to round a double to a 32-bit int explained
...,740,992 the representable numbers are exactly the integers
This follows from the fact that the mantissa is 52 bits wide.
The other interesting fact about adding 251+252 is that it affects the mantissa only in the two highest bits - which are discarded anyway, since we are taking only its lowest ...
String isNullOrEmpty in Java? [duplicate]
....isNotEmpty(str)
StringUtils.isBlank(str) or StringUtils.isNotBlank(str)
from Apache commons-lang.
The difference between empty and blank is : a string consisted of whitespaces only is blank but isn't empty.
I generally prefer using apache-commons if possible, instead of writing my own utility m...
Linq to EntityFramework DateTime
...as the EntityFunctions solution. Here, the second operand is not retrieved from another entity in query and can be computed prior to querying. If both operand were to be found in db, the EntityFunctions solution would still be suitable while the solution of this response would not work anymore.
...
Lists in ConfigParser
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There is nothing stopping you from packing the list into a delimited string and then unpacking it once you get the string from the config. If you did it this way your config section would look like:
[Section 3]
barList=item1,item2
It's not pretty but ...
Creating virtual directories in IIS express
...ion. Ex: iisexpress /site:WebSiteWithVirtualDirectory - run the first app from the path "C:\temp\website1". How can i run my the 2nd app that contains the path "d:\temp\SubFolderApp"
– Velu
Aug 29 '12 at 12:00
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Reading/writing an INI file
...ly like the same as what I've used for the past um-years of .Net. Upgraded from old code years ago.
– Damian
Jan 12 '17 at 15:03
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Check orientation on Android phone
...figuration, as used to determine which resources to retrieve, is available from the Resources' Configuration object:
getResources().getConfiguration().orientation;
You can check for orientation by looking at its value:
int orientation = getResources().getConfiguration().orientation;
if (orientat...
What is the difference between 'typedef' and 'using' in C++11?
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They are equivalent, from the standard (emphasis mine) (7.1.3.2):
A typedef-name can also be introduced by an alias-declaration. The
identifier following the using keyword becomes a typedef-name and the
optional attribute-specifier-seq fo...