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Rails DB Migration - How To Drop a Table?
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@mjnissim and fflyer05 are correct, in order to avoid any weird thing you should recreate the table in the down method.
– Sebastialonso
Jan 23 '15 at 16:43
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How to run a single test with Mocha?
...n) invocations.
Consider using nested describe() calls for namespacing in order to make it easy to locate and select particular sets.
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Block Comments in a Shell Script
...he above code would result in:
This is outside the commented block
In order to uncomment the code blocks thus commented, say
alias BEGINCOMMENT="if : ; then"
instead of
alias BEGINCOMMENT="if [ ]; then"
in the example above.
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Undefined method 'task' using Rake 0.9.0
...here is a problem in Rake 0.9.0. You need to temporarily downgrade Rake in order to avoid it:
run: gem uninstall rake -v 0.9 (add sudo unless you use rvm)
add to your Gemfile: gem 'rake', '~> 0.8.7'
and then run: bundle update
You can skip the first step, but then you have to run rake using b...
How to hide element using Twitter Bootstrap and show it using jQuery?
...tag. This happens prior to removing the hide class. If you have it in that order, it shouldn't flicker.
– Dustin Graham
Sep 16 '19 at 16:37
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Cosine Similarity between 2 Number Lists
... (more of a matrix transpose, actually) just to get the data in "Pythonic" order. It would be interesting to time the nuts-and-bolts implementation:
import math
def cosine_similarity(v1,v2):
"compute cosine similarity of v1 to v2: (v1 dot v2)/{||v1||*||v2||)"
sumxx, sumxy, sumyy = 0, 0, 0
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How to order by with union in SQL?
Is it possible to order when the data is come from many select and union it together? Such as
8 Answers
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Are global variables in PHP considered bad practice? If so, why?
...se that global variable, and not only that, you have to figure out in what order those references to the global variable are accessed.
If you have a global variable in a piece of code it makes it difficult to isolate the functionality of that code. Why would you want to isolate functionality? So yo...
Strtotime() doesn't work with dd/mm/YYYY format
... users question - it is a roundabout way of solving the actual problem. In order for strtotime() to properly parse a date in the format "dd/mm/yy", you need to replace the "/" with "-". Therefore you only really need the first two lines of the answer: $date = '25/05/2010'; $date = str_replace('/',...
How to verify if a file exists in a batch file?
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