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Numbering rows within groups in a data frame
...g this approach, make sure that you are not getting conflicts between plyr and dplyr as explained in this post It can be avoided by explicitly calling dplyr::mutate(...)
– EcologyTom
Apr 10 '18 at 14:16
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How to concatenate a std::string and an int?
...++11 (to_string() is already included in #include <string>)
is safe, and fast; requires FastFormat, which must be compiled; most/all platforms
(ditto)
is safe, and fast; requires the {fmt} library, which can either be compiled or used in a header-only mode; most/all platforms
safe, slow, and v...
Why are hexadecimal numbers prefixed with 0x?
Why are hexadecimal numbers prefixed as 0x ?
I understand the usage of the prefix but I don't understand the significance of why 0x was chosen.
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Execute another jar in a Java program
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If I understand correctly it appears you want to run the jars in a separate process from inside your java GUI application.
To do this you can use:
// Run a java app in a separate system process
Process proc = Runtime.getRuntime().exec...
How can I get the count of milliseconds since midnight for the current?
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and if somebody defines a timezone not on second border or adds a leap-millisecond this breaks.=))
– Markus Mikkolainen
Aug 2 '12 at 20:40
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How do I use the new computeIfAbsent function?
...t without a helper method (but you won’t see the debugging output then). And even simpler, as it is a simple delegation to an existing method you could write: whoLetDogsOut.computeIfAbsent("snoop", String::isEmpty); This delegation does not need any parameters to be written.
To be closer to the e...
What's the u prefix in a Python string?
...s that your string is a Unicode string.
Q: I'm in a terrible, awful hurry and I landed here from Google Search. I'm trying to write this data to a file, I'm getting an error, and I need the dead simplest, probably flawed, solution this second.
A: You should really read Joel's Absolute Minimum Ever...
What does it mean when an HTTP request returns status code 0?
...as not even headers were returned). This means the connection was accepted and then closed gracefully (TCP FIN).
There are a number of things which could cause this, but based off of your description, some form of firewall seems the most likely culprit.
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How to escape the % (percent) sign in C's printf?
... this won't work. \045 is compile-time escape that is part of the language and will turn into % when compiled. printf is a run-time function, so it deals with bytes of your string, not with C source code, and it has its own escape sequences that are parts of the function. In short, printf is a "lang...
What are the differences between JSON and JSONP?
Format wise, file type wise and practical use wise?
8 Answers
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