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Add timestamps to an existing table
..._table block. You can add these columns by specifying the column types manually:
class AddTimestampsToUser < ActiveRecord::Migration
def change_table
add_column :users, :created_at, :datetime, null: false
add_column :users, :updated_at, :datetime, null: false
end
end
While this do...
How to pull specific directory with git
...t saved me, so as far as I'm concerned, this is the correct answer - especially since this was a top hit on Google for this issue.
– Morgon
Nov 1 '11 at 14:39
21
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Heroku + node.js error (Web process failed to bind to $PORT within 60 seconds of launch)
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1043
Heroku dynamically assigns your app a port, so you can't set the port to a fixed number. Herok...
jQuery Datepicker onchange event issue
I have a JS code in which when you change a field it calls a search routine. The problem is that I can't find any jQuery events that will fire when the Datepicker updates the input field.
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How to count the number of true elements in a NumPy bool array
...xample:
>>> import numpy as np
>>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool)
>>> boolarr
array([[False, False, True],
[ True, False, True],
[ True, False, True]], dtype=bool)
>>> np.sum(boolarr)
5
Of course, that is ...
Where do I use delegates? [closed]
What are some real world places that call for delegates? I'm curious what situations or patterns are present where this method is the best solution. No code required.
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Why is document.write considered a “bad practice”?
...ctively writing serialised text which is not the way the DOM works conceptually, and is an easy way to create bugs (.innerHTML has the same problem)
Far better to use the safe and DOM friendly DOM manipulation methods
shar...
Conditional Replace Pandas
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.ix indexer works okay for pandas version prior to 0.20.0, but since pandas 0.20.0, the .ix indexer is deprecated, so you should avoid using it. Instead, you can use .loc or iloc indexers. You can solve this problem by:
mask = df.my_channel > 20000
column_name = 'my_chann...
Matplotlib tight_layout() doesn't take into account figure suptitle
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10 Answers
10
Active
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Rails: Using greater than/less than with a where statement
I'm trying to find all Users with an id greater than 200, but I'm having some trouble with the specific syntax.
9 Answers
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