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What's Pros and Cons: putting javascript in head and putting just before the body close
...er the page is visible to the user.
If you are adding styles or elements (etc. switching textfields with some form of richer editor) this will be visible to the user as flickering.
If you are adding click-events to elements, they will not be clickable until a bit after the elements themselves are ...
Add Keypair to existing EC2 instance
... lost your ssh key or forgot your password
You made a mistake editing the /etc/sudoers file and can no longer
gain root access with sudo to fix it
Your long running instance is hung for some reason, cannot be
contacted, and fails to boot properly
You need to recover files off of the instance but can...
In C#, can a class inherit from another class and an interface?
... I want to do this is because at my company we make USB, serial, Ethernet, etc device. I am trying to develop a generic component/interface that I can use to write programs for all our devices that will help keep the common things (like connecting, disconnecting, getting firmware) the same for all o...
Functional programming - is immutability expensive? [closed]
...storage in the form of stack space for the recursive step, which is in the order of O(log n) in the best case, but O(n) in the worst case.
Implementing a functional variant of quicksort that operates on arrays defeats the purpose. Arrays are never immutable.
The “proper” functional implementatio...
Why is `[` better than `subset`?
...adley suggests the following example: suppose we want to subset and then reorder a data frame using the following functions:
scramble <- function(x) x[sample(nrow(x)), ]
subscramble <- function(x, condition) {
scramble(subset(x, condition))
}
subscramble(mtcars, cyl == 4)
This returns t...
What is the bit size of long on 64-bit Windows?
... you call the 16-bit type? And if you call the 16-bit type char for UTF-16 etc, what do you call the 8-bit type? So, using LP64 leaves you with 8-bit char, 16-bit short, 32-bit int, 64-bit long, with room for upwards expansion to 128-bit long long when (if?) that becomes relevant. After that, you've...
When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
... all in one block.
BEGIN and END are just like { and } in C/++/#, Java, etc.
They bound a logical block of code. I tend to use BEGIN and END at the start and end of a stored procedure, but it's not strictly necessary there. Where it IS necessary is for loops, and IF statements, etc, where you ...
将 App Inventor 2 项目连接到外部传感器 · App Inventor 2 中文网
... port 13.
Ultrasonic sensors: port 36
Luminosity sensor: TwiMaster 1
In order to initialize all of the motors for use, the method “SetupMotors” must be called when the app starts and the screen is initialized. Here is an example of how simple the new blocks are to use:
Tutorials
A tutoria...
Zoom in on a point (using scale and translate)
...
var canvas = document.getElementById("canvas");
var context = canvas.getContext("2d");
var width = 600;
var height = 200;
var scale = 1;
var originx = 0;
var originy = 0;
var visibleWidth = width;
var visibleHeight = height;
function draw(){
// Clear screen to white.
con...
Escaping ampersand character in SQL string
...
In order to escape & you can try following ways:-
set scan off
set define off
set escape on
then replace & by/&
replace & by &&
One of them should work atleast.
Additionally if you are using PL/SQL ...