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Why does Double.NaN==Double.NaN return false?
...enormalized value or a signed zero, and an operation that has no mathematically definite result produces NaN. All numeric operations with NaN as an operand produce NaN as a result. As has already been described, NaN is unordered, so a numeric comparison operation involving one or two NaNs returns fa...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
...stcode , first name , last name , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(25...
Folder structure for a Node.js project
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Concerning the folders you mentioned:
/libs is usually used for custom classes/functions/modules
/vendor or /support contains 3rd party libraries (added as git
sub-module when using git as source control)
/spec contains specifications for BDD tests.
/tests contains the unit-...
javac option to compile all java files under a given directory recursively
...oject and don't have any proper build tools nearby, you can always use a small trick that javac offers: the classnames to compile can be specified in a file. You simply have to pass the name of the file to javac with the @ prefix.
If you can create a list of all the *.java files in your project, it'...
Reset the database (purge all), then seed a database
... the whole shebang just to reload your data, you could use MyModel.destroy_all (or delete_all) in the seed.db file to clean out a table before your MyModel.create!(...) statements load the data. Then, you can redo the db:seed operation over and over. (Obviously, this only affects the tables you've...
Installing R on Mac - Warning messages: Setting LC_CTYPE failed, using “C”
I would like install R on my laptop Mac OS X version 10.7.3
6 Answers
6
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Where are static variables stored in C and C++?
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@Don Neufeld: your answer does not answer the question at all. I do not understand why it is accepted. Because the both the 'foo' and 'bar' are non-0 initialized. The question is where to place two static/global variable with the same name in .bss or .data
– lu...
Convert xlsx to csv in Linux with command line
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The Gnumeric spreadsheet application comes with a command line utility called ssconvert that can convert between a variety of spreadsheet formats:
$ ssconvert Book1.xlsx newfile.csv
Using exporter Gnumeric_stf:stf_csv
$ cat newfile.csv
Foo,Bar,Baz
1,2,3
123.6,7.89,
2012/05/14,,
The,last,Line
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How to set warning level in CMake?
...CMake user should refrain from fiddling with CMAKE_CXX_FLAGS directly and call the target_compile_options command instead. Check the mrts' answer which presents the recommended best practice.
You can do something similar to this:
if(MSVC)
# Force to always compile with W4
if(CMAKE_CXX_FLAGS MA...
How to decompile a whole Jar file? [closed]
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2009: JavaDecompiler can do a good job with a jar: since 0.2.5, All files, in JAR files, are displayed.
See also the question "How do I “decompile” Java class files?".
The JD-Eclipse doesn't seem to have changed since late 2009 though (see Changes).
So its integration with latest Ecl...