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Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
Difference between Destroy and Delete
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Basically destroy runs any callbacks on the model while delete doesn't.
From the Rails API:
ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be ...
Specifying an Index (Non-Unique Key) Using JPA
...k: org.eclipse.persistence.annotations.Index;
DataNucleus: org.datanucleus.api.jpa.annotations.Index;
Carbonado (GitHub): com.amazon.carbonado.Index;
EBean: com.avaje.ebean.annotation.Index or io.ebean.annotation.Index ?
Ujorm: Annotation org.ujorm.orm.annot.Column, index and uniqueIndex properties;...
Is duplicated code more tolerable in unit tests?
...on is in the code manipulating the SUT, then ask yourself why multiple so-called “unit” tests are exercising the exact same functionality.
If the duplication is in the assertions, then perhaps you need some Custom Assertions. For example, if multiple tests have a string of assertions like:
as...
Are there best practices for (Java) package organization? [closed]
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Package organization or package structuring is usually a heated discussion. Below are some simple guidelines for package naming and structuring:
Follow java package naming conventions
Structure your packages according to their functional role as well as their business role...
Should I use Java date and time classes or go with a 3rd party library like Joda Time?
I'm creating a web based system which will be used in countries from all over the world. One type of data which must be stored is dates and times.
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Automatic post-registration user authentication
...istration flow: after the user creates an account, they should be automatically logged in with those credentials, instead of being immediately forced to provide their credentials again.
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What to use instead of “addPreferencesFromResource” in a PreferenceActivity?
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Still you need to call addPreferencesFromResource(int PreferencesID) if you want the app to be backwards compatible with api level erlier than 11 (Android 3.0). But I guess you could consider those old devices derecated as well.
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Role/Purpose of ContextLoaderListener in Spring?
...ates the WebApplicationContext. Otherwise it would need to be created manually.
– sourcedelica
Jul 26 '13 at 15:21
do...
How do I use Java to read from a file that is actively being written to?
...a channel for locking a part of a file.
http://java.sun.com/javase/6/docs/api/java/nio/channels/FileChannel.html
This function of the FileChannel might be a start
lock(long position, long size, boolean shared)
An invocation of this method will block until the region can be locked
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