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How to get current time and date in Android
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But where does this pull the date and time from? the android device setting itself?
– Kyle Clegg
May 17 '12 at 20:29
12
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Why does Double.NaN==Double.NaN return false?
...ith an IEEE-conforming float will produce false. So that standard differs from Java in that IEEE demands that (NAN != NAN) == false.
– Drew Dormann
Jan 17 '12 at 19:57
2
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Executing multi-line statements in the one-line command-line?
...- e.g., <<'EOF' - so as to protect the contents of the here-document from up-front shell expansions.
– mklement0
Apr 10 '15 at 15:11
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What is the difference between include and require in Ruby?
...can use
the load method.
The include method takes all the
methods from another module and
includes them into the current module.
This is a language-level thing as
opposed to a file-level thing as with
require. The include method is the
primary way to "extend" classes with
other ...
Is there a library function for Root mean square error (RMSE) in python?
..._error function. The RMSE is just the square root of whatever it returns.
from sklearn.metrics import mean_squared_error
from math import sqrt
rms = sqrt(mean_squared_error(y_actual, y_predicted))
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How to create SBT project with IntelliJ Idea?
...m/display/SCA/Scala+Plugin+for+IntelliJ+IDEA or can be installed directoly from within the IDE using Settings -> Plugins dialog. Afterwards one can just do File -> New Project -> Scala -> SBT based. IntelliJ will generate basic build.sbt, download necessary dependencies and open project....
Key hash for Android-Facebook app
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Here are the steps-
Download openssl from Google code (If you have a 64 bit machine you must download openssl-0.9.8e X64 not the latest version)
Extract it. create a folder- OpenSSL in C:/ and copy the extracted code here.
detect debug.keystore file path. If u d...
Creating an API for mobile applications - Authentication and Authorization
... of this in my projects is:
before login the user requests a login_token from the server. These are generated and stored on the server on request, and probably have a limited lifetime.
to login the application calculates the hash of the users password, then hashes the password with the login_token...
Get the real width and height of an image with JavaScript? (in Safari/Chrome)
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Use the naturalHeight and naturalWidth attributes from HTML5.
For example:
var h = document.querySelector('img').naturalHeight;
Works in IE9+, Chrome, Firefox, Safari and Opera (stats).
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How to design a database for User Defined Fields?
...define the data domains. Don't underestimate the performance hit resulting from on-the-fly data type conversion. Such
constraints also help RDBMS query
optimizers develop more effective
plans.
Should you ever need to use foreign
keys, built-in declarative
referential
integrity is rarely out-per...