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Looping through a hash, or using an array in PowerShell
...not; because I, like most people, like my code to run as fast as possible. Now, your argument is changing to running jobs in parallel (potentially using multiple computers/servers) ... which of course is faster than running a job in series from a single thread. Cheers!
– Vertig...
How do I delete rows in a data frame?
...a and have a look around and reorder the data. Your row deletion code will now delete the wrong rows, and worse, you are unlikely to get any errors warning you that this has occurred.
Better strategy
A better strategy is to delete rows based on substantive and stable properties of the row. For exa...
Efficient way to apply multiple filters to pandas DataFrame or Series
...ist or any iterable. We will create boolean variable just like before, but now we will negate the boolean variable by placing ~ in the front.
For example
list = [1, 0]
df[df.col1.isin(list)]
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How do RVM and rbenv actually work?
...d. Every Bash command that rbenv runs will be written to your terminal.
Now, rbenv is just concerned with switching versions, but a thriving ecosystem of plugins will help you do everything from installing Ruby to setting up your environment, managing "gemsets" and even automating bundle exec.
I...
Create a new database with MySQL Workbench
...alled the latest version of the MySQL Workbench (5.2.33). I would like to know how you can create a database with this application. In the Overview tab of the SQL editor there are few "MySQL Schema" displayed, are these schemas the existing databases?
...
What are the differences between “=” and “
...:
median((x = 1 : 10))
But also:
if (! (nf = length(from))) return()
Now you might object that such code is atrocious (and you may be right). But I took this code from the base::file.copy function (replacing <- with =) — it’s a pervasive pattern in much of the core R codebase.
The ori...
android pick images from gallery
... = context.getContentResolver().openInputStream(data.getData());
//Now you can do whatever you want with your inpustream, save it as file, upload to a server, decode a bitmap...
}
}
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How to reverse a string in Go?
... Wow, wtf is up with the double assignment when reversing? Interesting. Now, think about a string with an uneven number of runes. The middle one gets special treatment, with the correct end-result after all though. :) An interesting little optimization I wouldn’t have thought of right away.
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How to implement has_many :through relationships with Mongoid and mongodb?
...4684b7e9"),
"contact_ids" : [ ObjectId("4d3ed089fb60ab534684b7f2") ]
}
Now for a self-referencing Association in MongoDB, you have a few options.
has_many :related_contacts, :class_name => 'Contact', :inverse_of => :parent_contact
belongs_to :parent_contact, :class_name => 'Contact', ...
Grunt watch error - Waiting…Fatal error: watch ENOSPC
...
it didn't help, i tried with sudo and now it's working for me.
– asedsami
Jan 19 '16 at 1:19
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