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What does the “-U” option stand for in pip install -U
...ling, I can't find any docs for pip's command line options/arguments. What does pip install -U mean? Does anyone have a link to a list of pip's options and arguments?
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How to check if mysql database exists
...ts is:
SHOW DATABASES LIKE 'dbname';
If database with the name 'dbname' doesn't exist, you get an empty set. If it does exist, you get one row.
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TypeError: 'str' does not support the buffer interface
...riginal code worked for me under 3.1, and the sample code in the docs also does not encode explicitly. If you use it on non-ASCII text, does gunzip decompress it? I got an error.
– Tom Zych
Mar 29 '11 at 10:59
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What is std::promise?
... of several promises and associated futures and have a single thread which does several calculations and sets a result on each promise. async would only allow you to return a single result, to return several you would need to call async several times, which might waste resources.
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Why does “while(true)” without “Thread.sleep” cause 100% CPU usage on Linux but not on Windows?
..., top on Linux runs in so-called IRIX mode, while the Windows Task Manager does not. Let's say you have 4 cores:
With IRIX mode on, 1 fully utilized core is 100% and 4 cores are 400%.
With IRIX mode off, 1 fully utilized core is 25% and 4 cores are 100%.
This means that by default, top on Linu...
What is the difference between
... i have met somewhere in code this variant else <%== %> does anyone know what is it?
– okliv
Jul 11 '12 at 17:03
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What does the double colon (::) mean in CSS?
What does the double colon ( :: ) mean in CSS?
3 Answers
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Why does InetAddress.isReachable return false, when I can ping the IP address?
Why does isReachable return false ? I can ping the IP.
10 Answers
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Why does i = i + i give me 0?
... issue is due to integer overflow.
In 32-bit twos-complement arithmetic:
i does indeed start out having power-of-two values, but then overflow behaviors start once you get to 230:
230 + 230 = -231
-231 + -231 = 0
...in int arithmetic, since it's essentially arithmetic mod 2^32.
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How does one capture a Mac's command key via JavaScript?
How does one capture a Mac's Cmd key via JavaScript?
7 Answers
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