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Why is it important to override GetHashCode when Equals method is overridden?
...ce this is used (in the absence of a custom IEqualityComparer<T>) to group items into buckets. If the hash-code for two items does not match, they may never be considered equal (Equals will simply never be called).
The GetHashCode() method should reflect the Equals logic; the rules are:
if ...
Search all tables, all columns for a specific value SQL Server [duplicate]
...Name, ColumnName, ColumnValue, ColumnType, COUNT(*) AS Count FROM #Results
GROUP BY TableName, ColumnName, ColumnValue, ColumnType
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Why use String.Format? [duplicate]
...so the way five or more strings are joined via +s is by concatting them in groups of up to four, and then concatting those strings, and so on.
– octothorpentine
Aug 13 '15 at 18:46
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How do you build a Singleton in Dart?
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I also recommend reading this thread on the mailing list. groups.google.com/a/dartlang.org/d/msg/misc/9dFnchCT4kA/…
– Greg Lowe
May 21 '17 at 20:44
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Pandas aggregate count distinct
...13-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "user_id": pd.Series.nunique})
duration user_id
date
2013-04-01 65 2
2013-04-02 45 1
>>> df.groupby("date").a...
VIM Disable Automatic Newline At End Of File
...ld go into your .vimrc file:
autocmd! "Remove all autocmds (for current group), see below"
autocmd BufWritePost *.php !your-script <afile>
Be sure to read the whole vim documentation about autocommands if this is your first time dealing with autocommands. There are some caveats, e.g. it's...
Android adding simple animations while setvisibility(view.Gone)
...isibility(show ? View.VISIBLE : View.GONE);
}
Where parent is parent ViewGroup of animated view. Result:
Here is result with Slide transition:
import androidx.transition.Slide;
Transition transition = new Slide(Gravity.BOTTOM);
It is easy to write custom transition if you need something d...
How can I get a JavaScript stack trace when I throw an exception?
...if (Console.settings.stackTrace.collapsed)
console.groupCollapsed(sTitle, sCss);
else
console.group(sTitle, sCss);
console.debug("%c" + sLines, "color: #666666; font-style: italic;");
consol...
Python in Xcode 4+?
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If you do not have administrative privileges or are not in the Developer group, you can still use Xcode for Python programming (but you still won't be able to develop in languages that require compiling). Instead of using the play button, in the menu bar, click "Product" → "Perform Action" → "...
How do I wait for an asynchronously dispatched block to finish?
...n (which you'll make dependent upon the other operations). Or use dispatch groups. BTW, you say you don't want them running concurrently, which is fine if that's what you need, but you pay serious performance penalty doing this sequentially rather than concurrently. I generally use maxConcurrentOpe...