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Why does the order of the loops affect performance when iterating over a 2D array?
... x[1][0] etc...
Meaning that you're hitting them all in order. Now look at the 1st version. You're doing:
x[0][0]
x[1][0]
x[2][0]
x[0][1]
...
How do I get the logfile from an Android device?
...
Logcollector is a good option but you need to install it first.
When I want to get the logfile to send by mail, I usually do the following:
connect the device to the pc.
Check that I already setup my os for that particular device.
Open a terminal
Run adb shell logcat >...
javac is not recognized as an internal or external command, operable program or batch file [closed]
...nal or external command... error message.
In a nutshell, you have not installed Java correctly. Finalizing the installation of Java on Windows requires some manual steps. You must always perform these steps after installing Java, including after upgrading the JDK.
Environment variables and PATH
(...
Import CSV to SQLite
...l data. If that's the case with your CSV file, then you do not need to manually create the table using the create table command. The .import command will use the first line in your file to determine the column names and create the table accordingly. You still have to include the name of the table in...
Command to get time in milliseconds
...
date +%s%N returns the number of seconds + current nanoseconds.
Therefore, echo $(($(date +%s%N)/1000000)) is what you need.
Example:
$ echo $(($(date +%s%N)/1000000))
1535546718115
date +%s returns the number of seconds since the epoch, if that's useful.
...
What is the difference between is_a and instanceof?
...ut PHP versions >= 5.3.9 now accept an optional third boolean argument $allow_string (defaults to false) to allow comparisons of string class names instead:
class MyBaseClass {}
class MyExtendingClass extends MyBaseClass {}
// Original behavior, evaluates to false.
is_a(MyExtendingClass::class,...
Django Rest Framework File Upload
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Use the FileUploadParser, it's all in the request.
Use a put method instead, you'll find an example in the docs :)
class FileUploadView(views.APIView):
parser_classes = (FileUploadParser,)
def put(self, request, filename, format=None):
fi...
Copy folder recursively in node.js
Is there an easier way to copy a folder and all its content without manually doing a sequence of fs.readir , fs.readfile , fs.writefile recursively ?
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Create a GUID in Java
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@angel Yes, it is theoretically possible for the UUID.randomUUID method to return a duplicate, but this is not at all a realistic concern. The Oracle/OpenJDK implementation uses a cryptographically-strong random number generator. Given that, and given ...
苹果全球开发者大会：无硬件 iOS 9等三大系统更新 - 资讯 - 清泛网 - 专注C...
苹果全球开发者大会：无硬件 iOS 9等三大系统更新新浪手机讯 6月9日凌晨消息，2015年苹果全球开发者大会(WWDC 2015)在美国旧金山正式开幕，本届主题为the epicenter of change(变革的 新浪手机讯 6月9日凌晨消息，2015年苹果全球开发...