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Do I need dependency injection in NodeJS, or how to deal with …?
...eaddirSync method or you can return an entirely different module when you call require.
Method 1:
var oldmethod = fs.readdirSync;
fs.readdirSync = function(dir) {
return ['somefile.txt', 'error.txt', 'anotherfile.txt'];
};
*** PERFORM TEST ***
*** RESTORE METHOD AFTER TEST ****
fs.readddirS...
INSERT INTO…SELECT for all MySQL columns
... syntax, it looks like this (leave out the column list to implicitly mean "all")
INSERT INTO this_table_archive
SELECT *
FROM this_table
WHERE entry_date < '2011-01-01 00:00:00'
For avoiding primary key errors if you already have data in the archive table
INSERT INTO this_table_archive
SELECT...
What is your preferred style for naming variables in R? [closed]
...
Good previous answers so just a little to add here:
underscores are really annoying for ESS users; given that ESS is pretty widely used you won't see many underscores in code authored by ESS users (and that set includes a bunch of R Core as well as CRAN authors, excptions like Hadley notwithsta...
When should I use the Visitor Design Pattern? [closed]
...want to make the fewest possible modifications to it.
The Visitor pattern allows you to move each new operation in a suitable class, and you need to extend the hierarchy's interface only once. Let's do it. First, we define an abstract operation (the "Visitor" class in GoF) which has a method for ev...
What is the difference between class and instance methods?
...hen be used like so:
[MyClass aClassMethod];
MyClass *object = [[MyClass alloc] init];
[object anInstanceMethod];
Some real world examples of class methods are the convenience methods on many Foundation classes like NSString's +stringWithFormat: or NSArray's +arrayWithArray:. An instance method...
How can I get a precise time, for example in milliseconds in Objective-C?
...
Actually this is precise enough for the general use case.
– logancautrell
Jul 2 '12 at 12:30
4
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Convert a row of a data frame to vector
...
Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
How to check iOS version?
...system version as an indication of device or OS capabilities. There is usually a more reliable method of checking whether a particular feature or class is available.
Checking for the presence of APIs:
For example, you can check if UIPopoverController is available on the current device using NSCla...
Pandas conditional creation of a series/dataframe column
...
List comprehension is another way to create another column conditionally. If you are working with object dtypes in columns, like in your example, list comprehensions typically outperform most other methods.
Example list comprehension:
df['color'] = ['red' if x == 'Z' else 'green' for x in d...
Python: avoid new line with print command [duplicate]
...ork on 3.x, you suppress using print('whateverhere', end='') where end normally defaults to '\n'
– Jon Clements♦
Jun 29 '12 at 17:19
...
