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Performance of Find() vs. FirstOrDefault() [duplicate]
...his._items[index];
}
return default (T);
}
So it's iterating over an array of items which makes sense, since a list is a wrapper on an array.
However, FirstOrDefault, on the Enumerable class, uses foreach to iterate the items. This uses an iterator to the list and move next. I think what you...
How do I convert Long to byte[] and back in java
... ByteBuffer.allocate(Long.BYTES);
buffer.putLong(x);
return buffer.array();
}
public long bytesToLong(byte[] bytes) {
ByteBuffer buffer = ByteBuffer.allocate(Long.BYTES);
buffer.put(bytes);
buffer.flip();//need flip
return buffer.getLong();
}
Or wrapped in a class to avoi...
Javascript call() & apply() vs bind()?
...Smith says hello world"
apply is similar to call except that it takes an array-like object instead of listing the arguments out one at a time:
function personContainer() {
var person = {
name: "James Smith",
hello: function() {
console.log(this.name + " says hello " + argumen...
How to concatenate string variables in Bash
...tring, but also an integer
echo $a
24
((a+=12))
echo $a
36
Append to an array var+=(...)
Our a is also an array of only one element.
echo ${a[@]}
36
a+=(18)
echo ${a[@]}
36 18
echo ${a[0]}
36
echo ${a[1]}
18
Note that between parentheses, there is a space separated array. If you want to sto...
What does the “at” (@) symbol do in Python?
...mple, we would use this syntax to calculate the inner and outer product of arrays and matrices:
>>> from numpy import array, matrix
>>> array([[1,2,3]]).T @ array([[1,2,3]])
array([[1, 2, 3],
[2, 4, 6],
[3, 6, 9]])
>>> array([[1,2,3]]) @ array([[1,2,3]]).T
a...
Clean ways to write multiple 'for' loops
For an array with multiple dimensions, we usually need to write a for loop for each of its dimensions. For example:
16 An...
Generate random integers between 0 and 9
...
Choose the size of the array (in this example, I have chosen the size to be 20). And then, use the following:
import numpy as np
np.random.randint(10, size=(1, 20))
You can expect to see an output of the following form (different random inte...
Split a string by another string in C#
...
In order to split by a string you'll have to use the string array overload.
string data = "THExxQUICKxxBROWNxxFOX";
return data.Split(new string[] { "xx" }, StringSplitOptions.None);
share
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How to change color in circular progress bar?
...
If I have an array of colors and I want to set color to a color array on the each progress bar
– Prince
Aug 8 '18 at 7:44
...
How can I select from list of values in SQL Server
...
This is the most generic way, I was spoiled by unnest(ARRAY[]) in pgsql and now banging head to make FROM accept minor values as row records in sqlserver, and here it is. Happy to know.
– Ben
Oct 23 '17 at 9:49
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