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What does the ??!??! operator do in C?
...d-translated to ||, i.e the logical OR, by the preprocessor.
The following table containing every trigraph should help disambiguate alternate trigraph combinations:
Trigraph Replaces
??( [
??) ]
??< {
??> }
??/ \
??' ^
??= #
??! |
??- ...
Is there a CSS selector for elements containing certain text?
I am looking for a CSS selector for the following table:
18 Answers
18
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Display milliseconds in Excel
...
I've discovered in Excel 2007, if the results are a Table from an embedded query, the ss.000 does not work. I can paste the query results (from SQL Server Management Studio), and format the time just fine. But when I embed the query as a Data Connection in Excel, the format al...
MySQL - ORDER BY values within IN()
...
SELECT id, name
FROM mytable
WHERE name IN ('B', 'A', 'D', 'E', 'C')
ORDER BY FIELD(name, 'B', 'A', 'D', 'E', 'C')
The FIELD function returns the position of the first string in the remaining list of strings.
However, it is much better performan...
close vs shutdown socket?
...a.
close() decrements the descriptors reference count (maintained in file table entry and counts number of descriptors currently open that are referring to a file/socket) and does not close the socket/file if the descriptor is not 0. This means that if you are forking, the cleanup happens only afte...
Disable messages upon loading a package
...
not really, try library(data.table, quietly = TRUE)
– Gaurav Singhal
Jul 2 '18 at 8:40
add a comment
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What is the difference between an ORM and an ODM?
...a types so you can mix RDBMS and Document-oriented storage within the same table, including indexes and advanced query!
– Arnaud Bouchez
Jul 4 '14 at 11:21
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Check if Python Package is installed
...s:
import subprocess
import sys
reqs = subprocess.check_output([sys.executable, '-m', 'pip', 'freeze'])
installed_packages = [r.decode().split('==')[0] for r in reqs.split()]
The result:
print(installed_packages)
[
"Django",
"six",
"requests",
]
Check if requests is installed:
i...
Difference between . and : in Lua
...:method(arg) retrieves object only once. If object is a global, upvalue or table field, then : is faster than .. . is never faster than :.
– negamartin
Nov 5 '16 at 8:08
add a...
Adding a column to a data.frame
...number of groups (x in mapply) and its length (y in mapply)
mytb<-read.table(text="h_no h_freq h_freqsq group
1 0.09091 0.008264628 1
2 0.00000 0.000000000 1
3 0.04545 0.002065702 1
4 0.00000 0.000000000 1
1 0.13636 0.018594050 2
2 0.00000 0.000000000 2
3 0.00000 ...