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What does numpy.random.seed(0) do?
...thing every time you run it.
To get the most random numbers for each run, call numpy.random.seed(). This will cause numpy to set the seed to a random number obtained from /dev/urandom or its Windows analog or, if neither of those is available, it will use the clock.
For more information on using ...
What is a NullPointerException, and how do I fix it?
...sign it to the variable before trying to use the contents of the variable (called dereferencing). So you are pointing to something that does not actually exist.
Dereferencing usually happens when using . to access a method or field, or using [ to index an array.
If you attempt to dereference num BEF...
What is the difference between an expression and a statement in Python?
...rs, where operators include arithmetic and boolean operators, the function call operator () the subscription operator [] and similar, and can be reduced to some kind of "value", which can be any Python object. Examples:
3 + 5
map(lambda x: x*x, range(10))
[a.x for a in some_iterable]
yield 7
Sta...
R script line numbers at error?
...you the line number, but it will tell you where the failure happens in the call stack which is very helpful:
traceback()
[Edit:] When running a script from the command line you will have to skip one or two calls, see traceback() for interactive and non-interactive R sessions
I'm not aware of ano...
Detecting when the 'back' button is pressed on a navbar
...wController has TRUE value when I'm poping the navigation stack programmatically using popToRootViewControllerAnimated - without any touch on the back button. Should I downvote your answer? (the subject says "'back' button is pressed on a navbar")
– kas-kad
Jan...
“Java DateFormat is not threadsafe” what does this leads to?
...Java DateFormat not being thread safe and I understand the concept theoretically.
11 Answers
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How to trigger Autofill in Google Chrome?
... difficult for webmasters to ensure that Chrome and other form-filling providers can parse their form correctly. Some standards exist; but they put onerous burdens on the implementation of the website, so they’re not used much in practice.
(The "standards" they refer to is a more recent verion o...
What “things” can be injected into others in Angular.js?
... for telling Angular how to create new injectable things; these things are called services. Services are defined by things called providers, which is what you're creating when you use $provide. Defining a provider is done via the provider method on the $provide service, and you can get hold of the $...
A simple scenario using wait() and notify() in java
...simple scenario i.e. tutorial that suggest how this should be used, specifically with a Queue?
6 Answers
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How to generate a random int in C?
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Note: Don't use rand() for security. If you need a cryptographically secure number, see this answer instead.
#include <time.h>
#include <stdlib.h>
srand(time(NULL)); // Initialization, should only be called once.
int r = rand(); // Returns a pseudo-random integer be...