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C++11 emplace_back on vector?
...score_d: I'm not sure that I remember every detail of what I was thinking 3½ years ago, but I thinj what I was suggesting was that if you just use a tuple instead of defining a POD struct, then you get a constructor for free, which means that you get the emplace syntax for free (among other things ...
Django - how to create a file and save it to a model's FileField?
...s certainly a good solution, but here is the way I went about generating a CSV and serving it from a view.
Thought it was worth while putting this here as it took me a little bit of fiddling to get all the desirable behaviour (overwrite existing file, storing to the right spot, not creating duplica...
How can I convert comma separated string into a List
...ad of throwing an exception), here's something that uses TryParse:
string csv = "1,2,3,4,a,5";
int mos = 0;
var intList = csv.Split(',')
.Select(m => { int.TryParse(m, out mos); return mos; })
.Where(m => m != 0)
.ToList();
//return...
Version number comparison in Python
...(normalize(version1), normalize(version2))
This is the same approach as Pär Wieslander, but a bit more compact:
Here are some tests, thanks to "How to compare two strings in dot separated version format in Bash?":
assert mycmp("1", "1") == 0
assert mycmp("2.1", "2.2") < 0
assert mycmp("3.0.4...
Convert floats to ints in Pandas?
I've been working with data imported from a CSV. Pandas changed some columns to float, so now the numbers in these columns get displayed as floating points! However, I need them to be displayed as integers, or, without comma. Is there a way to convert them to integers or not display the comma?
...
How to get first 5 characters from string [duplicate]
...
substr("Häagen-Dazs", 0, 5) == "Häag" - what am i doing wrong?
– user187291
Sep 24 '10 at 13:32
12
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Way to read first few lines for pandas dataframe
Is there a built-in way to use read_csv to read only the first n lines of a file without knowing the length of the lines ahead of time? I have a large file that takes a long time to read, and occasionally only want to use the first, say, 20 lines to get a sample of it (and prefer not to load the...
C#中数组、ArrayList和List三者的区别 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...List< T> 始终只具有一个维度。但是，您可以轻松创建数组列表或列表的列表。特定类型（Object 除外）的数组 的性能优于 ArrayList的性能。 这是因为 ArrayList的元素属于 Object 类型；所以在存储或检索值类型时通常发生装箱和取消...
C#泛型(List)中基类和子类 怎么转换？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ChildClass> childList = ...Foo(List<BaseClass> baseList);需求：把子类列表传入函数Foo，Foo支持所有子类列表。方法一：Foo(ch...List<ChildClass> childList = ...
Foo(List<BaseClass> baseList);
需求：把子类列表传入函数Foo，Foo支持所有子类列表。
方法...
App Inventor 2 手机蓝牙及语音控制 - App Inventor 2 中文网 - 清泛IT论坛，有思想、有深度
...过程】 一、蓝牙知识准备
1. APP相关知识
列表选择框组件：便于用户从预设的条目中选择，如选择与手机配对的外部蓝牙设备；
蓝牙客户端组件：用于建立手机蓝牙与外部蓝牙设备的配对连接，并向外部蓝牙...