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What's the fastest way to loop through an array in JavaScript?
...yntactically obvious).
A standard for-loop with length caching
var i = 0, len = myArray.length;
while (i < len) {
// your code
i++
}
I would say, this is definitely a case where I applaud JavaScript engine developers. A runtime should be optimized for clarity, not cle...
CSS Progress Circle [closed]
... ones I have been able to found show animated circles that go to the full 100%.
4 Answers
...
Convert RGB to RGBA over white
...ha value.
Example:
152 converts to an alpha value of (255 - 152) / 255 ~ 0.404
152 scales using (152 - 152) / 0.404 = 0
177 scales using (177 - 152) / 0.404 ~ 62
202 scales using (202 - 152) / 0.404 ~ 123
So, rgb(152, 177, 202) displays as rgba(0, 62, 123, .404).
I have verified in Photoshop t...
Integrate ZXing in Android Studio
...ependencies {
implementation 'com.journeyapps:zxing-android-embedded:3.0.2@aar'
implementation 'com.google.zxing:core:3.2.0'
}
and Gradle does all the magic to compile the code and makes it accessible in your app.
To start the Scanner afterwards, use this class/method:
From the Activity:
...
Delete the first three rows of a dataframe in pandas
... |
edited Oct 17 '18 at 1:06
Acumenus
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answered...
How to add a new row to an empty numpy array
...
The way to "start" the array that you want is:
arr = np.empty((0,3), int)
Which is an empty array but it has the proper dimensionality.
>>> arr
array([], shape=(0, 3), dtype=int64)
Then be sure to append along axis 0:
arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr =...
List comprehension in Ruby
...1, 2, 3, 4, 5, 6]
new_array = some_array.comprehend {|x| x * 3 if x % 2 == 0}
puts new_array
Prints:
6
12
18
I would probably just do it the way you did though.
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improve this answer
...
What is the most efficient/elegant way to parse a flat table into a tree?
...
Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* F...
Suppress warning CS1998: This async method lacks 'await'
...
107
I've got an interface with some async functions.
Methods returning Task, I believe. async ...
Finding local IP addresses using Python's stdlib
How can I find local IP addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?
...