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Why is the shovel operator (
...g a new one. The reason for this is that in ruby a += b is syntactic shorthand for a = a + b (the same goes for the other <op>= operators) which is an assignment. On the other hand << is an alias of concat() which alters the receiver in-place.
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Add one row to pandas DataFrame
I understand that pandas is designed to load fully populated DataFrame but I need to create an empty DataFrame then add rows, one by one .
What is the best way to do this ?
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Fastest way to remove first char in a String
...foo" instead of "//foo".
The first option needs a bit more work to understand than the third - I would view the Substring option as the most common and readable.
(Obviously each of them as an individual statement won't do anything useful - you'll need to assign the result to a variable, possibly d...
Android View.getDrawingCache returns null, only null
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I was having this problem also and found this answer:
v.setDrawingCacheEnabled(true);
// this is the important code :)
// Without it the view will have a dimension of 0,0 and the bitmap will be null
v.measure(MeasureSpec.makeMeasureSpec(0, Me...
Why is setTimeout(fn, 0) sometimes useful?
...o initialize the drop-down list, ready to have its selected index updated, and
Your code to set the selected index
Your code was consistently winning this race and attempting to set drop-down selection before the browser was ready, meaning that the bug would appear.
This race existed because Java...
Check time difference in Javascript
...objects to get their difference:
// use a constant date (e.g. 2000-01-01) and the desired time to initialize two dates
var date1 = new Date(2000, 0, 1, 9, 0); // 9:00 AM
var date2 = new Date(2000, 0, 1, 17, 0); // 5:00 PM
// the following is to handle cases where the times are on the opposite si...
Find the PID of a process that uses a port on Windows
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Just open a command shell and type (saying your port is 123456):
netstat -a -n -o | find "123456"
You will see everything you need.
The headers are:
Proto Local Address Foreign Address State PID
TCP 0.0.0...
What is this operator in MySQL?
I'm working on code written by a previous developer and in a query it says,
9 Answers
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How can I make a div stick to the top of the screen once it's been scrolled to?
...s been scrolled enough to contact its top boundary, becomes fixed in place and scrolls with the page.
21 Answers
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android studio 0.4.2: Gradle project sync failed error
.......
This worked for me.
File -> Invalidate caches / Restart
Shutdown Android Studio
Rename/remove .gradle folder in the user home directory
Restart Android Studio let it download all the Gradle stuff it needs
Gradle build success !
Rebuild project.... success !
Out of curiousity I compared t...