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What is the difference between bottom-up and top-down?
... very rare cases*). This is like memoization but more active, and involves one additional step: You must pick, ahead of time, the exact order in which you will do your computations. This should not imply that the order must be static, but that you have much more flexibility than memoization.
examp...
Error: Tablespace for table xxx exists. Please DISCARD the tablespace before IMPORT
...ir /tmp/mysql_orphans
$ mv /var/lib/mysql/table3.ibd /tmp/mysql_orphans/
One caveat though, make sure what ever is causing the problem originally, e.g. long running query, locked table, etc... has been cleared. Otherwise you just end up with another orphaned .ibd file when you try a second time.
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How to find unused images in an Xcode project?
Has anyone a one-line to find unused images in an Xcode project? (Assuming all the files are referenced by name in code or the project files - no code generated file names.)
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Can you center a Button in RelativeLayout?
...elow. There are several ways to get the result you're looking for, this is one of the easier ways.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/relative_layout"
android:layout_width="fill_par...
arrayfun can be significantly slower than an explicit loop in matlab. Why?
...ut the computations, instead of using a function in your loop
tic
Soln3 = ones(T, N);
for t = 1:T
for n = 1:N
Soln3(t, n) = 3*x(t, n)^2 + 2*x(t, n) - 1;
end
end
toc
Time to compute on my computer:
Soln1 1.158446 seconds.
Soln2 10.392475 seconds.
Soln3 0.239023 seconds.
Oli ...
How to show “if” condition on a sequence diagram?
I was wondering, how can one represent " if " statement on a sequence diagram?
4 Answers
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Any reason not to use '+' to concatenate two strings?
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The assumption that one should never, ever use + for string concatenation, but instead always use ''.join may be a myth. It is true that using + creates unnecessary temporary copies of immutable string object but the other not oft quoted fact is...
How to tell if a string is not defined in a Bash shell script
... empty; fi
You probably can combine the two tests on the second line into one with:
if [ -z "$VAR" -a "${VAR+xxx}" = "xxx" ]; then echo VAR is set but empty; fi
However, if you read the documentation for Autoconf, you'll find that they do not recommend combining terms with '-a' and do recommend us...
How to get the nth element of a python list or a default if not available
...valent in python of dictionary.get(key, default) for lists. Is there any one liner idiom to get the nth element of a list or a default value if not available?
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Best way to alphanumeric check in JavaScript
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};
Of course, there may be other considerations, such as readability. A one-line regular expression is definitely prettier to look at. But if you're strictly concerned with speed, you may want to consider this alternative.
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