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SQLite Concurrent Access
Does SQLite3 safely handle concurrent access by multiple processes
reading/writing from the same DB? Are there any platform exceptions to that?
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Convert data.frame column format from character to factor
I would like to change the format (class) of some columns of my data.frame object ( mydf ) from charactor to factor .
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How can I read and parse CSV files in C++?
I need to load and use CSV file data in C++. At this point it can really just be a comma-delimited parser (ie don't worry about escaping new lines and commas). The main need is a line-by-line parser that will return a vector for the next line each time the method is called.
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Restore file from old commit in git
I have an old commit that I did a few weeks ago. I want to restore only a single file from that commit. What do I do?
4 Ans...
Mock HttpContext.Current in Test Init Method
I'm trying to add unit testing to an ASP.NET MVC application I have built. In my unit tests I use the following code:
4 An...
Mean per group in a data.frame [duplicate]
I have a data.frame and I need to calculate the mean per group (i.e. per Month , below).
8 Answers
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How do you use the Immediate Window in Visual Studio?
The Immediate Window is an immensely useful tool for debugging applications. It can be used to execute code statements that are valid in the context of a break point and inspect values. I also use it to type code snippets to learn language features.
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How to see if an NSString starts with a certain other string?
I am trying to check to see if a string that I am going to use as URL starts with http. The way I am trying to check right now doesn't seem to be working. Here is my code:
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What is the result of % in Python?
What does the % in a calculation? I can't seem to work out what it does.
19 Answers
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Argparse optional positional arguments?
I have a script which is meant to be used like this:
usage: installer.py dir [-h] [-v]
3 Answers
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