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Opposite of %in%: exclude rows with values specified in a vector
... use
`%not in%` <- function (x, table) is.na(match(x, table, nomatch=NA_integer_))
Another way is:
function (x, table) match(x, table, nomatch = 0L) == 0L
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Removing Java 8 JDK from Mac
So I installed the beta of JDK 8 a while ago to look at some of the examples. I thought for sure by now, it's easy to change between versions.
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Why is “copy and paste” of code dangerous? [closed]
...you will need to fix it every place you did and hope you can remember them all (this also holds for changed requirements).
If you keep logic in one place, it is easier to change when needed (so if you decide that the application needs updating, you only do it in one place).
Have your boss read abo...
Rails DB Migration - How To Drop a Table?
...tp://api.rubyonrails.org/classes/ActiveRecord/Migration.html
More specifically, you can see how to drop a table using the following approach:
drop_table :table_name
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Allowed memory size of 33554432 bytes exhausted (tried to allocate 43148176 bytes) in php
...austed. Maybe you don't need to read the whole file, maybe read it sequentially.
– macbirdie
Jan 22 '09 at 10:12
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Is the order of iterating through std::map known (and guaranteed by the standard)?
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Yes, that's guaranteed. Moreover, *begin() gives you the smallest and *rbegin() the largest element, as determined by the comparison operator, and two key values a and b for which the expression !compare(a,b) && !compare(b,a) is true are considered equal. The default comparis...
Examples of GoF Design Patterns in Java's core libraries
...FloatBuffer and DoubleBuffer)
javax.swing.GroupLayout.Group#addComponent()
All implementations of java.lang.Appendable
java.util.stream.Stream.Builder
Factory method (recognizeable by creational methods returning an implementation of an abstract/interface type)
java.util.Calendar#getInstance()
jav...
Return JSON response from Flask view
...om flask import jsonify
@app.route('/summary')
def summary():
d = make_summary()
return jsonify(d)
As of Flask 0.11, you can pass any JSON-serializable type, not just dict, as the top level object.
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What is Common Gateway Interface (CGI)?
...s the webserver how to pass data to and from an application. More specifically, it describes how request information is passed in environment variables (such as request type, remote IP address), how the request body is passed in via standard input, and how the response is passed out via standard ou...
C++ templates Turing-complete?
...n.
To turn out good programming using template meta-programming that is really useful for others to use (ie a library) is really really tough (though do-able). To Help boost even has MPL aka (Meta Programming Library). But try debugging a compiler error in your template code and you will be in for ...