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Do Java arrays have a maximum size?
...ry easy to test.
In a recent HotSpot VM, the correct answer is Integer.MAX_VALUE - 5. Once you go beyond that:
public class Foo {
public static void main(String[] args) {
Object[] array = new Object[Integer.MAX_VALUE - 4];
}
}
You get:
Exception in thread "main" java.lang.OutOfMemoryEr...
PostgreSQL Autoincrement
...other integer data type, such as smallint.
Example :
CREATE SEQUENCE user_id_seq;
CREATE TABLE user (
user_id smallint NOT NULL DEFAULT nextval('user_id_seq')
);
ALTER SEQUENCE user_id_seq OWNED BY user.user_id;
Better to use your own data type, rather than user serial data type.
...
How do you represent a JSON array of strings?
This is all you need for valid JSON, right?
4 Answers
4
...
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...
Collection was modified; enumeration operation may not execute
...
Is that a complete example? I have a class (_dictionary obj below) that contains a generic Dictionary<string,int> named MarkerFrequencies, but doing this didn't instantly solve the crash: lock (_dictionary.MarkerFrequencies) { foreach (KeyValuePair<string, int...
How to remove a directory from git repository?
...Remove duplicated directory"
git push origin <your-git-branch> (typically 'master', but not always)
Remove directory from git but NOT local
As mentioned in the comments, what you usually want to do is remove this directory from git but not delete it entirely from the filesystem (local)
In ...
SQL DROP TABLE foreign key constraint
If I want to delete all the tables in my database like this, will it take care of the foreign key constraint? If not, how do I take care of that first?
...
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
...
Using link_to with embedded HTML
...want a link in rails that uses that same icon class from twitter bootstrap all you need to do is something like this.
<%= link_to "Do it@", user_path(@user), :class => "btn icon-ok icon-white" %>
share
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...
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...