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How can I profile Python code line-by-line?
...0.4 while 1:
153 50000 69065 1.4 11.4 if Char1Glob == 'A':
154 50000 66354 1.3 10.9 IntLoc = IntLoc - 1
155 50000 67263 1.3 11.1 IntParIO = IntLoc - IntGlob
156 50000 65494 ...
Data Modeling with Kafka? Topics and Partitions
... of consumer so in the example above, I would just have a single topic and if you´ll decide to push some other kind of data through Kafka, you can add a new topic for that later.
Topics are registered in ZooKeeper which means that you might run into issues if trying to add too many of them, e.g. t...
What is the difference between the dot (.) operator and -> in C++? [duplicate]
What is the difference between the dot (.) operator and -> in C++?
14 Answers
14
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Ordering by specific field value first
...
There's also the MySQL FIELD function.
If you want complete sorting for all possible values:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core", "board", "other")
If you only care that "core" is first and the other values don't matter:
SELECT i...
Set margin size when converting from Markdown to PDF with pandoc
...ext, I used pandoc to convert the .md file into a PDF file (I get an error if I try and convert from the .html file). However, the PDF that is produced have massive margins (like this http://johnmacfarlane.net/pandoc/demo/example13.pdf ). How can I get pandoc to produce something with smaller mar...
Determine the number of NA values in a column
... @user3274289: although you'll usually want na.rm=TRUE, because otherwise if df$col contains NAs, sum will return NA.
– jbaums
Jun 4 '14 at 2:30
...
What's the valid way to include an image with no src?
...ources which won't cause server hits. I recently had a similar issue with iframes and determined //:0 to be the best option. No, really!
Starting with // (omitting the protocol) causes the protocol of the current page to be used, preventing "insecure content" warnings in HTTPS pages. Skipping th...
NSUserDefaults removeObjectForKey vs. setObject:nil
...
Swift 3.0
The below answer is no longer the case when I tested this.
When set to nil the result is NSCFData being stored. Possibly an NSNull object reference, but I am not positive.
To completely remove a value for a key use...
Is there any way to prevent input type=“number” getting negative values?
...Listen for input event on numInput.
number.onkeydown = function(e) {
if(!((e.keyCode > 95 && e.keyCode < 106)
|| (e.keyCode > 47 && e.keyCode < 58)
|| e.keyCode == 8)) {
return false;
}
}
<form action="" method="post">
<inp...
Is SecureRandom thread safe?
...afe implementation, and, from Java 7, explicitly guarantees threadsafety.
If many threads are using a single SecureRandom, there might be contention that hurts performance. On the other hand, initializing a SecureRandom instance can be relatively slow. Whether it is best to share a global RNG, or t...