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Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
...sider how negligible the penalty would have been if write was called on an array of 1m ints instead of on 1m times on one int. And in a real-life situation one would really appreciate the important features of IOStreams, namely its memory-safe and type-safe design. Such benefits come at a price, and...
schema builder laravel migrations unique on two columns
...
The second param is to manually set the name of the unique index. Use an array as the first param to create a unique key across multiple columns.
$table->unique(array('mytext', 'user_id'));
or (a little neater)
$table->unique(['mytext', 'user_id']);
...
Label encoding across multiple columns in scikit-learn
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As mentioned by larsmans, LabelEncoder() only takes a 1-d array as an argument. That said, it is quite easy to roll your own label encoder that operates on multiple columns of your choosing, and returns a transformed dataframe. My code here is based in part on Zac Stewart's excellen...
Creating a JSON response using Django and Python
...an object ("dictionary") at the top level, JSON is perfectly happy with an array at the top-level.
– Thanatos
Jun 20 '12 at 21:39
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Best way to parse command line arguments in C#? [closed]
...nd /b- for false) or by adding the value true/false, yes/no, etc.
Argument arrays: Simply add multiple values after the command-line name to set a property that is defined as an array. Ex, /x 1 2 3 will populate x with the array { 1, 2, 3 } (assuming x is defined as an array of integers).
Command-li...
Dynamic constant assignment
...e the value of a constant in a method, and your constant is a String or an Array, you can 'cheat' and use the #replace method to cause the object to take on a new value without actually changing the object:
class MyClass
BAR = "blah"
def cheat(new_bar)
BAR.replace new_bar
end
end
p MyCl...
Deep Learning（深度学习）学习笔记整理系列之（一） - 大数据 & AI - 清泛...
...低级抽象，逐渐向高级抽象迭代。人类的逻辑思维，经常使用高度抽象的概念。
例如，从原始信号摄入开始（瞳孔摄入像素 Pixels），接着做初步处理（大脑皮层某些细胞发现边缘和方向），然后抽象（大脑判定，眼前的...
What is the difference between Directory.EnumerateFiles vs Directory.GetFiles?
...collection is returned; when you use GetFiles, you must wait for the whole array of names to be returned before you can access the array. Therefore, when you are working with many files and directories, EnumerateFiles can be more efficient.
So basically, EnumerateFiles returns an IEnumerable which ...
How to return an empty ActiveRecord relation?
...ll not be any matches, but I still want to return a relation, not an empty array:
9 Answers
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How to overload functions in javascript?
...ument.
For variable numbers of arguments, you can use the arguments pseudo-array to access any given argument with arguments[i].
Here are some examples:
Let's look at jQuery's obj.data() method. It supports four different forms of usage:
obj.data("key");
obj.data("key", value);
obj.data();
obj....