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How to get the last char of a string in PHP?
...o get the last character of a string.
Say I have "testers" as input string and I want the result to be "s". how can I do that in PHP?
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How do you convert a byte array to a hexadecimal string, and vice versa?
How can you convert a byte array to a hexadecimal string, and vice versa?
45 Answers
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How do I undo the most recent local commits in Git?
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Undo a commit and redo
$ git commit -m "Something terribly misguided" # (1)
$ git reset HEAD~ # (2)
<< edit files as necessary >> # (3)
$ git add...
How to find Unused Amazon EC2 Security groups
...'m try to find a way to determine orphan security groups so I can clean up and get rid of them. Does anyone know of a way to discover unused security groups.
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Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
I guess I'm not clear on how to do "and" tests. I wanted to make sure an argument existed which was working well with [ -e $VAR ] , but it turns out that was also evaluating as true on an empty string; which I do not want.
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Is short-circuiting logical operators mandated? And evaluation order?
Does the ANSI standard mandate the logical operators to be short-circuited, in either C or C++?
7 Answers
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How to execute a raw update sql with dynamic binding in rails
... to do this generically. You could try accessing the underlying connection and using it's methods, e.g. for MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("update table set f1=? where f2=? and f3=?")
st.execute(f1, f2, f3)
st.close
I'm not sure if there are other ramifications t...
Dealing with “Xerces hell” in Java/Maven?
... users are "touched" by this problem at some point. Unfortunately, understanding the problem requires a bit of knowledge about the history of Xerces...
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Is it possible to use argsort in descending order?
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If you negate an array, the lowest elements become the highest elements and vice-versa. Therefore, the indices of the n highest elements are:
(-avgDists).argsort()[:n]
Another way to reason about this, as mentioned in the comments, is to observe that the big elements are coming last in the ar...
What are DDL and DML?
I have heard the terms DDL and DML in reference to databases, but I don't understand what they are.
12 Answers
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