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How big is too big for a PostgreSQL table?
... 3 we create the cluster, this basically puts the DB table in the physical order of the index, so when postgresql performs a query it caches the most likely next rows. Step 4 we vacuum the database to reset the statistics for the query planner
– James Doherty
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Why use softmax as opposed to standard normalization?
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The values of q_i represent log-likelihoods. In order to recover the probability values, you need to exponentiate them.
One reason that statistical algorithms often use log-likelihood loss functions is that they are more numerically stable: a product of probabilities may ...
Spark java.lang.OutOfMemoryError: Java heap space
... longer need to play with these values, spark will determine them automatically.
Similar to above but shuffle memory fraction. If your job doesn't need much shuffle memory then set it to a lower value (this might cause your shuffles to spill to disk which can have catastrophic impact on speed). So...
Rotated elements in CSS that affect their parent's height correctly
...phs for easier visualiation: */
background: pink;
margin: 1px 0;
border: 1px solid black;
}
.rotation-wrapper-outer {
display: table;
}
.rotation-wrapper-inner {
padding: 50% 0;
height: 0;
}
.element-to-rotate {
display: block;
transform-origin: top left;
/* Note: fo...
Why should the “PIMPL” idiom be used? [duplicate]
...() to be able to use private members of CatImpl. Cat::Purr() would not be allowed such an access without a friend declaration.
Because you then don't mix responsibilities: one class implements, one class forwards.
share...
filter for complete cases in data.frame using dplyr (case-wise deletion)
...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
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Removing Java 8 JDK from Mac
So I installed the beta of JDK 8 a while ago to look at some of the examples. I thought for sure by now, it's easy to change between versions.
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Redirecting to a relative URL in JavaScript
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How can I tell jackson to ignore a property for which I don't have control over the source code?
... my entities has a GeometryCollection that throws an exception when you call "getBoundary" (the why of this is another book, for now let's say this is the way it works).
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Prepend text to beginning of string
...aterial changes of note that you made to the tests? A prepend is just the ordered half of string concatenation. Also, for jsPerf, you don't need to throw the test cases in a loop; jsPerf call each method thousands of times to get a baseline of scores. Perf tests optimize particular scenarios, and...