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Can an enum class be converted to the underlying type?
...
I think you can use std::underlying_type to know the underlying type, and then use cast:
#include <type_traits> //for std::underlying_type
typedef std::underlying_type<my_fields>::type utype;
utype a = static_cast<utype>(my_fields::field);
With th...
Mean per group in a data.frame [duplicate]
..."Rate2"), row.names = c(NA, -9L), class = c("data.table", "data.frame"))
Now to take the mean of Rate1 and Rate2 for all 3 months, for each person (Name):
First, decide which columns you want to take the mean of
colstoavg <- names(mydt)[3:4]
Now we use lapply to take the mean over the column...
scheduleAtFixedRate vs scheduleWithFixedDelay
... executor.shutdown()
} else {
Thread.sleep(2000L)
val now = System.currentTimeMillis()
time += now - start
System.out.println("Total $time delay ${now - start}\n")
start = now
}
}, 0L, 1000L, TimeUnit.MILLISECONDS)
And see the results:
| scheduleWi...
Can (domain name) subdomains have an underscore “_” in it?
...s only one restriction on the particular labels
that can be used to identify resource records. That one
restriction relates to the length of the label and the full
name. [...] Implementations of the DNS protocols must not place any
restrictions on the labels that can be used. In particular...
Why is the gets function so dangerous that it should not be used?
...
In order to use gets safely, you have to know exactly how many characters you will be reading, so that you can make your buffer large enough. You will only know that if you know exactly what data you will be reading.
Instead of using gets, you want to use fgets, whi...
“The breakpoint will not currently be hit. The source code is different from the original version.”
... cardinal sin, as that config may well be used by the CI build machine (I know it is here), so ultimately could pass that when it should fail. I know it could be one of many build steps but still... @Oliver I hope the team member bought you some biscuits ! :)
– Fetchez la vache...
What is the volatile keyword useful for?
...ome code continues a loop. The loop tests the volatile value and continues if it is true. The condition can be set to false by calling a "stop" method. The loop sees false and terminates when it tests the value after the stop method completes execution.
The book "Java Concurrency in Practice," whic...
Nested defaultdict of defaultdict
...
One note. If you are trying to use this code while pickling lambda won't work.
– Viacheslav Kondratiuk
Apr 3 '17 at 11:52
...
What are “connecting characters” in Java identifiers?
...t i = Character.MIN_CODE_POINT; i <= Character.MAX_CODE_POINT; i++)
if (Character.isJavaIdentifierStart(i) && !Character.isAlphabetic(i))
System.out.print((char) i + " ");
}
prints
$ _ ¢ £ ¤ ¥ ؋ ৲ ৳ ৻ ૱ ௹ ฿ ៛ ‿ ⁀ ⁔ ₠ ₡ ₢ ₣ ₤ ₥ ₦ ₧ ...
Storing SHA1 hash values in MySQL
...es just 4 bit per character and thus would need 160/4 = 40 characters. But if you use 8 bit per character, you would only need a 160/8 = 20 character long field.
So I recommend you to use BINARY(20) and the UNHEX function to convert the SHA1 value to binary.
I compared storage requirements for BIN...