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How do I get an empty array of any size in python?
I basically want a python equivalent of this in C:
8 Answers
8
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Determine the number of NA values in a column
...unt the number of NA values in a data frame column. Say my data frame is called df , and the name of the column I am considering is col . The way I have come up with is following:
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Array include any value from another array?
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(cheeses & foods).empty?
As Marc-André Lafortune said in comments, & works in linear time while any? + include? will be quadratic. For larger sets of data, linear time will be faster. For small data sets, any? + include? may be faster as shown by Lee Jarvis' answer -- pro...
How to pip install a package with min and max version range?
... var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled...
How to make the tab character 4 spaces instead of 8 spaces in nano?
...use nano with a language like python (as in your example) it's also a good idea to convert tabs to spaces.
Edit your ~/.nanorc file (or create it) and add:
set tabsize 4
set tabstospaces
If you already got a file with tabs and want to convert them to spaces i recommend the expandcommand (shell):...
jquery-ui-dialog - How to hook into dialog close event
... Jake N - You need to actually write a function accessible to the dialog called 'CloseFunction' for this to work, for example just above you could write var CloseFunction = function() { //Do your custom closing stuff here };
– Adam Diament
Jul 24 '14 at 18:0...
JavaScript: remove event listener
... if(click == 50) {
this.removeEventListener('click',arguments.callee,false);
}
Should do it.
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How to convert date to timestamp?
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There are two problems here.
First, you can only call getTime on an instance of the date. You need to wrap new Date in brackets or assign it to variable.
Second, you need to pass it a string in a proper format.
Working example:
(new Date("2012-02-26")).getTime();
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Difference between Array and List in scala
...hich fast random access is important.
Mutable Structures
ListBuffer provides a constant-time conversion to a List which is reason alone to use ListBuffer if such later conversion is required.
A scala Array should be implemented on the JVM by a Java array, and hence an Array[Int] may be much more...
Creating stored procedure and SQLite?
...client/server (NOT SQLite!), For these, performance is a key issue when deciding where to put your business logic. Executing business logic be it query OR interative OR conditional code inside an SP in the SQL engine can (1) improve data retrieval performance, (2) reduce network traffic (3) reduce ...