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How to initialise memory with new operator in C++?
I'm just beginning to get into C++ and I want to pick up some good habits. If I have just allocated an array of type int with the new operator, how can I initialise them all to 0 without looping through them all myself? Should I just use memset ? Is there a “C++” way to do it?
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Difference between numeric, float and decimal in SQL Server
What are the differences between numeric , float and decimal datatypes and which should be used in which situations?
8...
HTML5 Local storage vs. Session storage
Apart from being non persistent and scoped only to the current window, are there any benefits (performance, data access, etc) to Session Storage over Local Storage?
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How can I rename a database column in a Ruby on Rails migration?
...mething else or do nothing
end
end
For Rails 3.1 use:
While, the up and down methods still apply, Rails 3.1 receives a change method that "knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method".
See "Active Record...
How do I check in JavaScript if a value exists at a certain array index?
... element with index i is defined to be part of the array if i is between 0 and array.length - 1 inclusive. If i is not in this range it's not in the array.
So by concept, arrays are linear, starting with zero and going to a maximum, without any mechanism for having "gaps" inside that range where n...
How to create a release signed apk file using Gradle?
...KEY_ALIAS=*****
RELEASE_KEY_PASSWORD=*****
Modify your app/build.gradle, and add this inside the android { code block:
...
signingConfigs {
release {
storeFile file(RELEASE_STORE_FILE)
storePassword RELEASE_STORE_PASSWORD
keyAlias RELEASE_KEY_ALIAS
keyPassword ...
How to load/edit/run/save text files (.py) into an IPython notebook cell?
... individual cells of an open IPython notebook so that they can edited, run and then saved. Can this be done?
4 Answers
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How to get a pixel's x,y coordinate color from an image?
...ur PNG. The following creates an off-screen canvas that is the same width and height as your image and has the image drawn on it.
var img = document.getElementById('my-image');
var canvas = document.createElement('canvas');
canvas.width = img.width;
canvas.height = img.height;
canvas.getContext('2...
How to automatically select all text on focus in WPF TextBox?
If I call SelectAll from a GotFocus event handler, it doesn't work with the mouse - the selection disappears as soon as mouse is released.
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Declaring variables inside loops, good practice or bad practice?
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The compiler knows that the variable scope is limited to inside the loop, and therefore will issue a proper error message if the variable is by mistake referenced elsewhere.
Last but not least, some dedicated optimization can be performed more efficiently by the compiler (most importantly register ...