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How to get the last N rows of a pandas DataFrame?
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This is because of using integer indices (ix selects those by label over -3 rather than position, and this is by design: see integer indexing in pandas "gotchas"*).
*In newer versions of pandas prefer loc or iloc to remove the ambiguity of ix as position or label:
df....
How is a tag different from a branch in Git? Which should I use, here?
...;" would generate anonymous unnamed branch (so called 'detached HEAD') and select state of tag. Creating a new commit does it on this unnamed branch, and does not change what tag points to.
– Jakub Narębski
Feb 16 '12 at 14:04
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How to remove all the null elements inside a generic list in one go?
...ach, but it brings a surprise to the developer who just thinks that OfType selects objects of a certain type, not thinking that it will not include null values ... So I'm a bit weary to introduce this into my own code.
– user3638471
Apr 12 '16 at 21:14
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not:first-child selector
... the versions you posted actually works for all modern browsers (where CSS selectors level 3 are supported):
div ul:not(:first-child) {
background-color: #900;
}
If you need to support legacy browsers, or if you are hindered by the :not selector's limitation (it only accepts a simple selector...
Detect If Browser Tab Has Focus
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onblur|.blur/onfocus|.focus "duplicate" calls
window losing focus through selection of alternate app, like word
This tends to be undesirable simply because, if you have a bank page open, and it's onblur event tells it to mask the page, then if you open calculator, you can't see the page anymore!
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Avoiding SQL injection without parameters
...ion is wrong. You need to put apostrophes around the text:
string sql = "SELECT * FROM Users WHERE Name='" + SafeDBString(name) & "'";
SqlCommand getUser = new SqlCommand(sql, connection);
So that's one other thing parameters do for you: you don't need to worry about whether or not a value ...
Gmail Error :The SMTP server requires a secure connection or the client was not authenticated. The s
... Yes, the reason is 2 steps verification switched On for gmail account. Select App/Device and click Generate button support.google.com/accounts/answer/185833
– smily
Dec 25 '15 at 15:34
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How do you use bcrypt for hashing passwords in PHP?
...pt works internally. And there are a TON of answers about that. Here are a selection that I've written, that I won't copy/paste here, but link to:
Fundamental Difference Between Hashing And Encryption Algorithms - Explaining the terminology and some basic information about them.
About reversing ha...
What does “dereferencing” a pointer mean?
...he pointer may be relative to some specific memory area, which the CPU may select based on CPU "segment" registers or some manner of segment id encoded in the bit-pattern, and/or looking in different places depending on the machine code instructions using the address.
For example, an int* properly ...
How to put Google Maps V2 on a Fragment using ViewPager
...le way
first log in to your google account and visit google libraries and select Google Maps Android API
dependency found in android studio default map activity :
compile 'com.google.android.gms:play-services:10.0.1'
put your key into android mainifest file under application like below
in Andr...