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Replace all 0 values to NA
... has a 0 value which should be considered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
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How to capitalize the first letter in a String in Ruby
...рия".capitalize #=> мария
The problem is, it just doesn't do what you want it to, it outputs мария instead of Мария.
If you're using Rails there's an easy workaround:
"мария".mb_chars.capitalize.to_s # requires ActiveSupport::Multibyte
Otherwise, you'll have to instal...
What is the purpose of setting a key in data.table?
...hich require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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What is the direction of stack growth in most modern systems?
....org/wiki/Calling_convention
See also
Why does the stack grow downward?
What are the advantages to having the stack grow downward?
Why do stacks typically grow downwards?
Does stack grow upward or downward?
share
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How do I convert from int to String?
... smell as it suggests the author doesn't know about the two methods above (what else might they not know?).
Java has special support for the + operator when used with strings (see the documentation) which translates the code you posted into:
StringBuilder sb = new StringBuilder();
sb.append("");
s...
What should I set JAVA_HOME environment variable on macOS X 10.6?
Many Java applications that use shell scripts to configure their environment use the JAVA_HOME environment variable to start the correct version of Java, locate JRE JARs, and so on.
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What is the use of “assert” in Python?
...nswer get so many up votes, actually others answers also. the question is "What is the use of “assert” in Python? ", so it is asking: when to use, or more exactly: what is the usage scenario of assert, but after reading all answers, i totally got nothing i want!
– lnshi
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What is the correct format to use for Date/Time in an XML file
What format do I use for Date/Time when writing to an XML file using .NET? Do I simply use DateTime.ToString() , or do I have to use a specific format?
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What's the “average” requests per second for a production web application?
I have no frame of reference in terms of what's considered "fast"; I'd always wondered this but have never found a straight answer...
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What's the difference between Require.js and simply creating a element in the DOM? [closed]
What's the difference between using Require.JS amd simply creating a <script> element in the DOM?
4 Answers
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