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Rails DB Migration - How To Drop a Table?
... ActiveRecord::Migration
def change
drop_table :users do |t|
t.string :email, null: false
t.timestamps null: false
end
end
end
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Asynchronous Requests with Python requests
...and then asking a loop to execute those tasks and exit upon completion. No extra libraries subject to lack of maintenance, no lack of functionality required.
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How to write LaTeX in IPython Notebook?
...vec{\mathbf{B}} & = 0
\end{align}
Math object to pass in a raw LaTeX string:
from IPython.display import Math
Math(r'F(k) = \int_{-\infty}^{\infty} f(x) e^{2\pi i k} dx')
Latex class. Note: you have to include the delimiters yourself. This allows you to use other LaTeX modes such as eqnarra...
How to add property to a class dynamically?
...ing on. Better late than never.
You can add a property to a class dynamically. But that's the catch: you have to add it to the class.
>>> class Foo(object):
... pass
...
>>> foo = Foo()
>>> foo.a = 3
>>> Foo.b = property(lambda self: self.a + 1)
>>&...
PHP Multidimensional Array Searching (Find key by specific value)
...;
Will produce:
array(2) {
[5]=>
array(2) {
["foo"]=>
string(5) "test4"
["bar"]=>
string(4) "baz1"
}
[10]=>
array(2) {
["foo"]=>
string(5) "test4"
["bar"]=>
string(4) "baz1"
}
}
...
Is there any sed like utility for cmd.exe? [closed]
...:
get-content somefile.txt | where { $_ -match "expression"}
or
select-string somefile.txt -pattern "expression"
and for sed there is:
get-content somefile.txt | %{$_ -replace "expression","replace"}
For more detail see Zain Naboulsis blog entry.
...
How to use CURL via a proxy?
... data will be returned to $curl_scraped_page variable.
I removed a second extra curl_exec($ch); which would stop the variable being returned.
I consolidated your proxy IP and port into one setting.
I also removed CURLOPT_HTTPPROXYTUNNEL and CURLOPT_CUSTOMREQUEST as it was the default.
If you don'...
How can I handle time zones in my webapp?
...
The majority of your users probably will not change timezones much, or at all. For the most part, the situation you outlined is uncommon. By implementing a dropdown with a suitable default, you should be able to make things easy enough for those who do move around (because they typically have a bet...
Grid of responsive squares
...creating a layout with responsive squares . Each square would have vertically and horizontally aligned content. The specific example is displayed below...
...
What's the difference between streams and datagrams in network programming?
...ets
stream (TCP, order and delivery guaranteed,no duplication,no length or char boundaries for data,connection-oriented,reliable, concurrency)
datagram(UDP,packet-based, connectionless, datagram size limit, data can be lost or duplicated, order not guaranteed,not reliable)
raw (direct access to lowe...