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Why does base64 encoding require padding if the input length is not divisible by 3?
What is the purpose of padding in base64 encoding. The following is the extract from wikipedia:
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How can I make setuptools install a package that's not on PyPI?
I've just started working with setuptools and virtualenv. My package requires the latest python-gearman that is only available from GitHub. The python-gearman version that's on PyPI is an old one. The Github source is setuptools-compatible, i.e. has setup.py, etc. Is there a way to make setuptools d...
When do I use a dot, arrow, or double colon to refer to members of a class in C++?
Coming from other C-derived languages (like Java or C#) to C++, it is at first very confusing that C++ has three ways to refer to members of a class: a::b , a.b , and a->b . When do I use which one of these operators?
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How do you delete a column by name in data.table?
To get rid of a column named "foo" in a data.frame , I can do:
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stringstream, string, and char* conversion confusion
My question can be boiled down to, where does the string returned from stringstream.str().c_str() live in memory, and why can't it be assigned to a const char* ?
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Python: json.loads returns items prefixing with 'u'
I'll be receiving a JSON encoded string form Obj-C, and I am decoding a dummy string (for now) like the code below. My output comes out with character 'u' prefixing each item:
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Is there a Unix utility to prepend timestamps to stdin?
I ended up writing a quick little script for this in Python, but I was wondering if there was a utility you could feed text into which would prepend each line with some text -- in my specific case, a timestamp. Ideally, the use would be something like:
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what exactly is device pixel ratio?
this is mentioned every article about mobile web, but nowhere I can found an explanation of what exactly does this attribute measure.
Can anyone please elaborate what does queries like this check?
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What is the meaning of the term arena in relation to memory?
I'm reading a book on memory as a programming concept. In one of the later chapters, the author makes heavy use of the word arena , but never defines it. I've searched for the meaning of the word and how it relates to memory, and found nothing. Here are a few contexts in which the author uses the...
How to “warm-up” Entity Framework? When does it get “cold”?
No, the answer to my second question is not the winter.
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