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C# 'is' operator performance
...rt performance if, once you check the type, you cast to that type. is actually casts the object to the type you are checking so any subsequent casting is redundant.
If you are going to cast anyway, here is a better approach:
ISpecialType t = obj as ISpecialType;
if (t != null)
{
// use t her...
SQLite DateTime comparison
...e a few datetime functions. Follow the string representation formats (actually only formats 1-10) understood by those functions (storing the value as a string) and then you can use them, plus lexicographical comparison on the strings will match datetime comparison (as long as you don't try to compa...
Scatterplot with too many points
...;- data.frame(x = rnorm(5000),y=rnorm(5000))
ggplot(df,aes(x=x,y=y)) + geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning:
ggplot(df,aes(x=x,y=y)) + stat_binhex()
And there is also regula...
How to deploy a war file in Tomcat 7
I have copied the sample.war file into the webapps directory of Tomcat, and I can access localhost:8080 .
12 Answers
...
Inserting data into a temporary table
...
To insert all data from all columns, just use this:
SELECT * INTO #TempTable
FROM OriginalTable
Don't forget to DROP the temporary table after you have finished with it and before you try creating it again:
DROP TABLE #TempTable
...
Can I change multiplier property for NSLayoutConstraint?
...them, since "Activating or deactivating the constraint calls addConstraint(_:) and removeConstraint(_:) on the view that is the closest common ancestor of the items managed by this constraint".
– qix
Jan 4 '17 at 5:26
...
How to get nice formatting in the Rails console
...he y method is a handy way to get some pretty YAML output.
y ProductColor.all
Assuming you are in script/console
As jordanpg commented, this answer is outdated. For Rails 3.2+ you need to execute the following code before you can get the y method to work:
YAML::ENGINE.yamler = 'syck'
From rub...
How to convert a string to number in TypeScript?
..., or simply use the unary + operator:
var x = "32";
var y: number = +x;
All of the mentioned techniques will have correct typing and will correctly parse simple decimal integer strings like "123", but will behave differently for various other, possibly expected, cases (like "123.45") and corner c...
How to safely call an async method in C# without await
...it completes, then you can do this:
public string GetStringData()
{
var _ = MyAsyncMethod();
return "hello world";
}
BTW, this is not a "common problem". It's very rare to want to execute some code and not care whether it completes and not care whether it completes successfully.
Update:
Sin...
那些曾被追捧的90后创业男神女神，还好吗？ - 资讯 - 清泛网 - 专注C/C++及内核技术
...不新鲜。
案例链接：http://emglook.com/play-17240?from=timeline&isappinstalled=0
质疑二：宣传片盗用
并且在云视链的宣传内容里，居然有不少其他公司做的案例。http://www.avdmg.com/cn
质疑三：高管资料疑伪造
2.昙花一现的“脸萌”
脸萌...