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bash: pip: command not found
I downloaded pip and ran python setup.py install and everything worked just fine. The very next step in the tutorial is to run pip install <lib you want> but before it even tries to find anything online I get an error "bash: pip: command not found".
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Null check in an enhanced for loop
...ecause an empty list won't fail.
If you get this list from somewhere else and don't know if it is ok or not you could create a utility method and use it like this:
for( Object o : safe( list ) ) {
// do whatever
}
And of course safe would be:
public static List safe( List other ) {
ret...
Stretch and scale a CSS image in the background - with CSS only
I want that my background image stretch and scale depending on the browser viewport size.
22 Answers
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Can I apply the required attribute to fields in HTML5?
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Mandatory: Have the first value empty - required works on empty values
Prerequisites: correct html5 DOCTYPE and a named input field
<select name="somename" required>
<option value="">Please select</option&g...
How do I parse JSON with Ruby on Rails? [duplicate]
I'm looking for a simple way to parse JSON, extract a value and write it into a database in Rails.
12 Answers
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How to simulate the environment cron executes a script with?
... Good, simple idea. For the impatient use '* * * * *' to run next minute, and remember to turn off again when you are done playing ;-)
– Mads Buus
Mar 12 '13 at 19:26
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Fragments within Fragments
I'm wondering if this is actually a bug in the Android API:
6 Answers
6
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Remove an entire column from a data.frame in R
...on't need drop argument cause it always return data.frame from data.frame. And I think this is much better way to localized columns (and only columns) in data.frame (and it's faster). Check: cars[-1] (one col data.frame) or better cars[-(1:2)]: data frame with 0 columns and 50 rows.
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How can I maximize the editor pane in IntelliJ IDEA?
...the editor pane to make the editor pane take up the entire Eclipse window, and then again to restore the pane back to its previous size exposing the other panes.
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Is the SQL WHERE clause short-circuit evaluated?
...er expressions are actually evaluated left to right, particularly when operands or operators might
cause conditions to be raised or if the results of the expressions
can be determined without completely evaluating all parts of the
expression.
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