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Is there a more elegant way of adding an item to a Dictionary safely?
... throw) and the indexer otherwise. (It's a bit like the difference between casting and using as for reference conversions.)
If you're using C# 3 and you have a distinct set of keys, you can make this even neater:
var currentViews = new Dictionary<string, object>()
{
{ "Customers", "view2...
Row count with PDO
... count($nRows); - count() is an array function :P. I'd also recommend type casting the result from fetchColumn() to an integer. $count = (int) $stmt->fetchColumn()
– Cobby
May 26 '11 at 23:59
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String concatenation vs. string substitution in Python
...ou are profiling how. For one your concat is slow because you have two str casts in it. With strings the result is the opposite, since string concat is actually faster than all the alternatives when only three strings are concerned.
– Justus Wingert
Sep 16 '15 ...
PHP - Merging two arrays into one array (also Remove Duplicates)
...hird argument. If it is not a string, or the contents cannot be implicitly cast to a string, you will need the SORT_REGULAR argument.
– David Baucum
Aug 19 '16 at 19:33
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Preserving order with LINQ
... You can map a source element by index to a result element
AsEnumerable
Cast
Concat
Select
ToArray
ToList
Preserves Order. Elements are filtered or added, but not re-ordered.
Distinct
Except
Intersect
OfType
Prepend (new in .net 4.7.1)
Skip
SkipWhile
Take
TakeWhile
Where
Zip (new in .net 4)
...
Gets byte array from a ByteBuffer in java
...gned integers, only signed ones. If you want "unsigned bytes", you need to cast as int and use a bitmask: int unsigned_byte = b[k] & 0xff; for some value of k.
– Jason S
Apr 15 '17 at 2:13
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make arrayList.toArray() return more specific types
...lass[myList.size()])?
If your list is not properly typed you need to do a cast before calling toArray. Like this:
List l = new ArrayList<String>();
String[] a = ((List<String>)l).toArray(new String[l.size()]);
...
how to show progress bar(circle) in an activity having a listview before loading the listview with d
...ists. SO, in the AsyncTask's onPreExecute() I use something like this:
// CAST THE LINEARLAYOUT HOLDING THE MAIN PROGRESS (SPINNER)
LinearLayout linlaHeaderProgress = (LinearLayout) findViewById(R.id.linlaHeaderProgress);
@Override
protected void onPreExecute() {
// SHOW THE SPINNER WHILE ...
Differences between fork and exec
...he "exec" functions to create the child process
execvp (argv[0], const_cast<char**>(argv));
} else { // This is the Parent Process
//Continue executing parent process
}
share
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R - Concatenate two dataframes?
... Nice. I just wanted to post the same answer :-) . One improvement: @Anton casted the NA to double in his answer. It would be nice when the type of the new column was the same type as the existing column in the other data frame. Maybe via mode(d2[d2.add[i]]) <- mode(d1[d2.add[i]]). But I am not s...