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HTML: How to limit file upload to be only images?
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answered Oct 13 '09 at 19:32
Ms2gerMs2ger
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Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
...for how to best divide data into training and validation sets? Is an even 50/50 split advisable? Or are there clear advantages of having more training data relative to validation data (or vice versa)? Or is this choice pretty much application dependent?
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jQuery add image inside of div tag
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302
Have you tried the following:
$('#theDiv').prepend('<img id="theImg" src="theImg.png" />...
When should I use @classmethod and when def method(self)?
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70
Your guess is correct - you understand how classmethods work.
The why is that these methods can...
How to create duplicate allowed attributes
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answered Feb 16 '09 at 14:59
Anton GogolevAnton Gogolev
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Run a callback only if an attribute has changed in Rails
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200
Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_chan...
How to randomly pick an element from an array
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Chris DennettChris Dennett
20.9k88 gold badges5050 silver badges8181 bronze badges
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What is the best way to use a HashMap in C++?
...gt;first << " Value: " << i->second << '\n';
return 0;
}
Output:
23
Key: hello Value: 23
If you need ordering in your container and are fine with the O(log n) runtime then just use std::map.
Otherwise, if you really need a hash-table (O(1) insert/access), check out std:...
Python: How would you save a simple settings/config file?
...er()
– user3148949
Apr 27 '17 at 6:40
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lock(new object()) — Cargo cult or some crazy “language special case”?
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edited Aug 20 '12 at 13:43
sehe
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