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Apache Spark: The number of cores vs. the number of executors
I'm trying to understand the relationship of the number of cores and the number of executors when running a Spark job on YARN.
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Signed to unsigned conversion in C - is it always safe?
...unsigned values, resulting in a large result (depending on the values of u and i).
Long Answer
According to the C99 Standard:
6.3.1.8 Usual arithmetic conversions
If both operands have the same type, then no further conversion is needed.
Otherwise, if both operands have signed intege...
What does yield mean in PHP?
...eturn statement, except that instead of stopping execution of the function and returning, yield instead provides a value to the code looping over the generator and pauses execution of the generator function.
What is a generator function?
A generator function is effectively a more compact and effi...
Use RSA private key to generate public key?
I don't really understand this one:
9 Answers
9
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Non greedy (reluctant) regex matching in sed?
...that don't work this way for sure, e.g. when parsing URL for its host part and pathname with final slash assumed optional to be excluded from capturing: ^(http:\/\/.+?)/?$
– Thomas Urban
Mar 17 at 8:40
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What's the fastest way to loop through an array in JavaScript?
...dern browsers:
https://jsben.ch/wY5fo
Currently, the fastest form of loop (and in my opinion the most syntactically obvious).
A standard for-loop with length caching
var i = 0, len = myArray.length;
while (i < len) {
// your code
i++
}
I would say, this is definitely ...
How to shrink/purge ibdata1 file in MySQL
... new table (B), import the data into B, submit a query to get what I need, and then I drop B and drop A.
8 Answers
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Getting the first and last day of a month, using a given DateTime object
I want to get the first day and last day of the month where a given date lies in. The date comes from a value in a UI field.
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How do you match only valid roman numerals with a regular expression?
...L|L?X{0,3})(IX|IV|V?I{0,3})$
Breaking it down, M{0,4} specifies the thousands section and basically restrains it to between 0 and 4000. It's a relatively simple:
0: <empty> matched by M{0}
1000: M matched by M{1}
2000: MM matched by M{2}
3000: MMM matched by M{3}
4000:...
Best way to merge two maps and sum the values of same key?
I want to merge them, and sum the values of same keys. So the result will be:
15 Answers
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