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How to check whether a pandas DataFrame is empty?
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This seems like a shame, since you need to know that df is a pd.DataFrame. I'd like to know the motivation for not implementing bool() on pd.DataFrame.
– Quant
Feb 14 '14 at 16:55
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Initializing C# auto-properties [duplicate]
... bar;
}
}
It's unfortunate that there's no way of doing this right now. You have to set the value in the constructor. (Using constructor chaining can help to avoid duplication.)
Automatically implemented properties are handy right now, but could certainly be nicer. I don't find myself wanti...
Vim: Delete buffer without losing the split window
...ch is so simple, not requiring and entire script to run it. In my VIMRC, I now have this mapped for CTRL+C: nnoremap <C-c> :bp\|bd #<CR>
– Cloud
Jul 12 '13 at 17:40
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#ifdef #ifndef in Java
...with "final" modifier Java compiler itself solves the problem. Because it knows in advance what would be the result of testing this condition.
For example this code:
boolean flag1 = true;
boolean flag2 = false;
int j=0;
for(int i=0;i<1000000000;i++){
if(flag1)
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Get the device width in javascript
...max-width value of the html tag:
maxwidth = $('html').css('max-width');
Now you can use this value to make conditional changes:
If (maxwidth == '480px') { do something }
If putting the max-width value on the html tag seems scary, then maybe you can put on a different tag, one that is only used...
Inserting multiple rows in mysql
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@RPK. I agree with you but I don't know her data source. As I already wrote, if she has a file, I would use load data syntax as cularis suggests. :)
– Nicola Cossu
Jul 31 '11 at 11:54
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C++ valarray vs. vector
I like vectors a lot. They're nifty and fast. But I know this thing called a valarray exists. Why would I use a valarray instead of a vector? I know valarrays have some syntactic sugar, but other than that, when are they useful?
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generate model using user:references vs user_id:integer
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how does rails know that user_id is a foreign key referencing user?
Rails itself does not know that user_id is a foreign key referencing user. In the first command rails generate model Micropost user_id:integer it only adds a column user_i...
How do I create a slug in Django?
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utf-8 is now handled correctly by slugify (in django 1.8.5)
– Rick Westera
Nov 20 '15 at 23:53
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How do I grep recursively?
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It is good to know that "-i" would make it case insensitive, and "-n" also include the line number for each matched result.
– Sadegh
Jan 23 '15 at 12:02
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