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in iPhone App How to detect the screen resolution of the device
In iPhone App,
while running the App on device How to detect the screen resolution of the device on which App is running?
6...
Rails: How to get the model class name based on the controller class name?
...will do it:
class HouseBuyersController < ApplicationController
def index
@model_name = controller_name.classify
end
end
This is often needed when abstracting controller actions:
class HouseBuyersController < ApplicationController
def index
# Equivalent of @house_buyers = ...
UIPopovercontroller dealloc reached while popover is still visible
I assure you that I did look for an answer in SO for my question but none of them were helpful. Here I got a simple code that should present a UIImagePickerController within a UIPopoverController :
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Change how fast “title” attribute's tooltip appears
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No, there's no way. The title attribute is implemented in a browser dependent fashion. For example I remember differences between IE and FF when using \r\n inside it.
Mozilla's docs explain the limits and functionality well.
If you want customization you may take a look at thi...
PostgreSQL - Rename database
I need to rename the database but when I do in
PGAdmin : ALTER DATABASE "databaseName" RENAME TO "databaseNameOld" it told me that it cannot.
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Creating a new column based on if-elif-else condition
...lse:
val = -1
return val
Then apply it to your dataframe passing in the axis=1 option:
In [1]: df['C'] = df.apply(f, axis=1)
In [2]: df
Out[2]:
A B C
a 2 2 0
b 3 1 1
c 1 3 -1
Of course, this is not vectorized so performance may not be as good when scaled to a large num...
List tables in a PostgreSQL schema
When I do a \dt in psql I only get a listing of tables in the current schema ( public by default).
4 Answers
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How do I revert master branch to a tag in git?
We have branches origin and develop.
The initial state of master was tagged at tag_ABC .
2 Answers
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Erratic hole type resolution
I recently found out that type holes combined with pattern matching on proofs provides a pretty nice Agda-like experience in Haskell. For example:
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Rails migrations: self.up and self.down versus change
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For many operations rails can guess what is the inverse operation (without problems). For example, in your case what is the reverse operation of add_column to call when you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in ...