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JS - get image width and height from the base64 code
...ve a base64 img encoded that you can find here . How can I get the height and the width of it?
4 Answers
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C++ Object Instantiation
I'm a C programmer trying to understand C++. Many tutorials demonstrate object instantiation using a snippet such as:
9 An...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...ND_ROWS?
Just a quick summary: Peter says that it depends on your indexes and other factors. Many of the comments to the post seem to say that SQL_CALC_FOUND_ROWS is almost always slower - sometimes up to 10x slower - than running two queries.
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What's the most efficient way to erase duplicates and sort a vector?
...to take a C++ vector with potentially a lot of elements, erase duplicates, and sort it.
23 Answers
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How many and which are the uses of “const” in C++?
...y obscure to me, one of these is const . You can use it in so many places and with so many different effects that is nearly impossible for a beginner to come out alive. Will some C++ guru explain once forever the various uses and whether and/or why not to use them?
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IIS Express Windows Authentication
...ption-1:
edit \My Documents\IISExpress\config\applicationhost.config file and enable windowsAuthentication, i.e:
<system.webServer>
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<security>
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<authentication>
<windowsAuthentication enabled="true" />
</authentication>
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</security>
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What is the difference between a HashMap and a TreeMap? [duplicate]
...mple of a SortedMap, which means that the order of the keys can be sorted, and when iterating over the keys, you can expect that they will be in order.
HashMap on the other hand, makes no such guarantee. Therefore, when iterating over the keys of a HashMap, you can't be sure what order they will b...
Is using Random and OrderBy a good shuffle algorithm?
...t an O(n) shuffle. The code in the question "works" by basically giving a random (hopefully unique!) number to each element, then ordering the elements according to that number.
I prefer Durstenfield's variant of the Fisher-Yates shuffle which swaps elements.
Implementing a simple Shuffle extensio...
Scanning Java annotations at runtime [closed]
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Use org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider
API
A component provider that scans the classpath from a base package. It then applies exclude and include filters to the resulting classes to find candidates.
ClassPathScanningCandidateComp...