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How to take the first N items from a generator or list in Python? [duplicate]
...imple syntax: array[start:stop:step]
You can omit any parameter. These are all valid: array[start:], array[:stop], array[::step]
Slicing a generator
import itertools
top5 = itertools.islice(my_list, 5) # grab the first five elements
You can't slice a generator directly in Python. itertools.i...
jQuery set radio button
... jQuery 1.6 the perferred method of altering a property is .prop(): http://api.jquery.com/prop
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“where 1=1” statement [duplicate]
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It's usually when folks build up SQL statements.
When you add and value = "Toyota" you don't have to worry about whether there is a condition before or just WHERE. The optimiser should ignore it
No magic, just practical
Example ...
Drop all tables whose names begin with a certain string
How can I drop all tables whose names begin with a given string?
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Git - fatal: Unable to create '/path/my_project/.git/index.lock': File exists
... directory. The error message is rather explicit as to what causes it typically, so if you have no other git processes running (which is the normal case), go ahead and delete that file.
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Automatic HTTPS connection/redirect with node.js/express
...ng to get HTTPS set up with a node.js project I'm working on. I've essentially followed the node.js documentation for this example:
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Cast Int to enum in Java
... 0 or 1, i.e. a valid ordinal for that enum.
Note that in Java enums actually are classes (and enum values thus are objects) and thus you can't cast an int or even Integer to an enum.
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Vim: insert the same characters across multiple lines
...e the screen in the first line - until Esc is pressed (6.), at which point all lines will be updated.
Press Esc.
An uppercase I must be used rather than a lowercase i, because the lowercase i is interpreted as the start of a text object, which is rather useful on its own, e.g. for selecting insi...
Does adding a duplicate value to a HashSet/HashMap replace the previous value
...do a check on the backing HashMap to see if the key already exists before calling put on the backing map?
– mystarrocks
Jun 9 '14 at 21:36
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Python Pandas: Get index of rows which column matches certain value
... frame (whose data may be gibabytes). What about dftest? Doesn't this also allocate a very large intermediate object where the returned index may be very small, or even empty. Are these magically optimized away using lazy views. If not then surely there must be an efficient way.
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