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Performance of FOR vs FOREACH in PHP
First of all, I understand in 90% of applications the performance difference is completely irrelevant, but I just need to know which is the faster construct. That and...
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What's the Hi/Lo algorithm?
...ke up a primary key- a "high" number and a "low" number. A client can basically increment the "high" sequence, knowing that it can then safely generate keys from the entire range of the previous "high" value with the variety of "low" values.
For instance, supposing you have a "high" sequence with a...
Why does one hot encoding improve machine learning performance?
...e. The three possible values of w×x are 0, w and 2×w. Either these three all lead to the same decision (they're all < b or ≥b) or "UK" and "French" lead to the same decision, or "French" and "US" give the same decision. There's no possibility for the model to learn that "UK" and "US" should b...
Get source JARs from Maven repository
...e" afterwards and then refresh your project in eclipse--saves you from manually attaching sources to each file.
– unigeek
Apr 3 '14 at 15:06
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How does Apple find dates, times and addresses in emails?
...ay be wrong). On the other hand I'd except the naiive approach of encoding all common formats to perform way better (possibly 0.99+ given that the most frequent formats will never be missed) and to be faster to implement + at runtime.
– b.buchhold
Feb 25 '12 at...
“unadd” a file to svn before commit
...Ok, I guess you and I understand this phrase differently: without deleting all the documents. Unfortunately, svn revert does also delete the newly added changes in the working copy, by restoring the lastest HEAD version. I removed my downvote, but I still feel the warning is important.
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image processing to improve tesseract OCR accuracy
... highly pixellated - for example that generated by fax machines - is especially difficult for tesseract to process - presumably all those jagged edges to the characters confound the shape-recognition algorithms.
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How do you delete a column by name in data.table?
...hod 3 (could then assign to df3,
df3[, !"foo"]
though if you were actually wanting to remove column "foo" from df3 (as opposed to just printing a view of df3 minus column "foo") you'd really want to use Method 1 instead.
(Do note that if you use a method relying on grep() or grepl(), you need ...
How to use 'find' to search for files created on a specific date? [closed]
...nted out by Max, you can't, but checking files modified or accessed is not all that hard. I wrote a tutorial about this, as late as today. The essence of which is to use -newerXY and ! -newerXY:
Example: To find all files modified on the 7th of June, 2007:
$ find . -type f -newermt 2007-06-07 ! -...
How to close TCP and UDP ports via windows command line
...t the remote machine, the network card, the network cable, and your OS can all cause the socket to close.
Consider also that Fiddler and Desktop VPN software can insert themselves into the network stack and show you all your traffic or reroute all your traffic.
So all you really need is either fo...