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How to extract img src, title and alt from html using php? [duplicate]
...exps :
<img[^>]+>
We apply it on all html web pages. It can be read as every string that starts with "<img", contains non ">" char and ends with a >.
(alt|title|src)=("[^"]*")
We apply it successively on each img tag. It can be read as every string starting with "alt", "title...
Select first 4 rows of a data.frame in R
... character (matching the respective names):
df[row.index, column.index]
Read help(`[`) for more detail on this subject, and also read about index matrices in the Introduction to R.
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NOW() function in PHP
... be working and yours is also nice, but does not help, as the guy asking already knew a way how to do it, but wanted an easier, single-purpose function, which yours is not :)
– Asped
Jan 22 '15 at 11:24
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How does database indexing work? [closed]
...the address of the actual record, which requires a further block access to read, bringing the total to 19 + 1 = 20 block accesses, a far cry from the 1,000,000 block accesses required to find a firstName match in the non-indexed table.
When should it be used?
Given that creating an index requires ...
How to use OpenSSL to encrypt/decrypt files?
... Do not use the above command since there is no key derivation. Read more here: openssl weak key derivation
– jonasl
Apr 29 '16 at 13:25
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Embedding DLLs in a compiled executable
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Wow - I thought I finally found it, then I read this comment. It seems to be gone totally. Are there any forks?
– Mafii
Oct 8 '16 at 16:19
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String.Empty versus “” [duplicate]
...e a lot of time thinking about it. Choose based on whatever you find more readable, or whatever convention is already being used in your project.
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Which one will execute faster, if (flag==0) or if (0==flag)?
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I haven't seen any correct answer yet (and there are already some) caveat: Nawaz did point out the user-defined trap. And I regret my hastily cast upvote on "stupidest question" because it seems that many did not get it right and it gives room for a nice discussion on compiler op...
How to safely open/close files in python 2.4
...ry-finally blocks:
>>> with open('workfile', 'r') as f:
... read_data = f.read()
>>> f.closed
True
More here: https://docs.python.org/2/tutorial/inputoutput.html#methods-of-file-objects
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Difference between GeoJSON and TopoJSON
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And even though I did remember reading about "shared line segments", I still assumed "topo" stood for "topography", which it does not. Here's a nice read about the difference between "topology" and "topography" (the former is the origin of "topo" in topojs...