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How to compare two floating point numbers in Bash?

...) )); then … fi Explanation Piping through the basic calculator command bc returns either 1 or 0. The option -l is equivalent to --mathlib; it loads the standard math library. Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or...
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Can I set variables to undefined or pass undefined as an argument?

I’m a bit confused about JavaScript’s undefined and null values. 10 Answers 10...
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Is it better to use std::memcpy() or std::copy() in terms to performance?

...ll have a slight, almost imperceptible performance loss. I just did a test and found that to be untrue: I did notice a performance difference. However, the winner was std::copy. I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and ...
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What are the differences between Helper and Utility classes?

...ts more common. A Utility class is understood to only have static methods and be stateless. You would not create an instance of such a class. A Helper can be a utility class or it can be stateful or require an instance be created. I would avoid this if possible. If you can make the name more spe...
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How do I flush the PRINT buffer in TSQL?

...long-running stored procedure in SQL Server 2005 that I'm trying to debug, and I'm using the 'print' command to do it. The problem is, I'm only getting the messages back from SQL Server at the very end of my sproc - I'd like to be able to flush the message buffer and see these messages immediately d...
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Which SQL query is faster? Filter on Join criteria or Where clause?

... Performance-wise, they are the same (and produce the same plans) Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN. In your very case this will look like this: SELECT * FROM TableA a LEFT JOIN ...
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Why does Lua have no “continue” statement?

I have been dealing a lot with Lua in the past few months, and I really like most of the features but I'm still missing something among those: ...
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How do SO_REUSEADDR and SO_REUSEPORT differ?

The man pages and programmer documentations for the socket options SO_REUSEADDR and SO_REUSEPORT are different for different operating systems and often highly confusing. Some operating systems don't even have the option SO_REUSEPORT . The WEB is full of contradicting information regarding th...
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what is the difference between a portlet and a servlet?

I am asked to work on portlets and portals. 5 Answers 5 ...
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Determine if the device is a smartphone or tablet? [duplicate]

... This subject is discussed in the Android Training: Use the Smallest-width Qualifier If you read the entire topic, they explain how to set a boolean value in a specific value file (as res/values-sw600dp/attrs.xml): <resources> <bool name="isTa...