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Remove an element from a Bash array
...ating over them backwards (so deleting elements doesn't screw up iteration order). To get the indices you need to access the input array by name, which can be done via bash variable indirection x=1; varname=x; echo ${!varname} # prints "1".
You can't access arrays by name like aryname=a; echo "${$a...
DistutilsOptionError: must supply either home or prefix/exec-prefix — not both
I've been usually installed python packages through pip.
8 Answers
8
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How to use clock() in C++
How do I call clock() in C++ ?
7 Answers
7
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Output array to CSV in Ruby
...e number of k/v pairs & that the keys are always the same, in the same order (i.e. if your data is structured), this should do the deed:
rowid = 0
CSV.open(fn, 'w') do |csv|
hsh_ary.each do |hsh|
rowid += 1
if rowid == 1
csv << hsh.keys# adding header row (column labels)
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Is null reference possible?
...
References are not pointers.
8.3.2/1:
A reference shall be initialized to
refer to a valid object or function.
[Note: in particular, a null reference
cannot exist in a well-defined
program, because the only way to
create such a reference would be to
bind it to the ...
Pros and cons of Java rules engines [closed]
...stablished algorithms (such as forward chaining and the Rete algorithm) in order to scale up to non-trivial problems. If you are simply evaluating expressions, an existing library such as MVEL may be useful.
– jevon
Feb 28 '11 at 6:19
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Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
Where does PostgreSQL store the database?
...here the data directory is, use this query.
show data_directory;
To see all the run-time parameters, use
show all;
You can create tablespaces to store database objects in other parts of the filesystem. To see tablespaces, which might not be in that data directory, use this query.
SELECT * FRO...
HTML anchor link - href and onclick both?
...href attribute, I'd return "-1" to prevent the default action, which is usually the browser jumping tot he top of the page, or sometimes I'd just not return anything. Lately I've had to revise all those pages as @Amber advised... to specifically return false, if I don't want the page to jump.
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Trying to fire the onload event on script tag
I'm trying to load a set of scripts in order, but the onload event isn't firing for me.
1 Answer
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