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Access an arbitrary element in a dictionary in Python
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for a non-destructive popitem you can make a (shallow) copy: key, value = dict(d).popitem()
– Pelle
Jan 31 '18 at 10:35
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open read and close a file in 1 line of code
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You don't really have to close it - Python will do it automatically either during garbage collection or at program exit. But as @delnan noted, it's better practice to explicitly close it for various reasons.
So, what you can do to keep ...
How to check if hex color is “too black”?
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You have to extract the three RGB components individually, and then use a standard formula to convert the resulting RGB values into their perceived brightness.
Assuming a six character colour:
var c = c.substring(1); // strip #
var rgb = parseInt(c, 16); // convert rrg...
no new variables on left side of :=
...e is also a "short variable declaration" ( http://golang.org/ref/spec#Short_variable_declarations ) which means that in the left we need to have at least a new variable declaration for it to be correct.
You can change the second to a simple assignment statement := -> = or you can use a new varia...
Getting “unixtime” in Java
... platforms (and the year 2038 problem). 64-bit platforms use a larger time_t data type. Java dodged that bullet by using a long as the return for System.currentTimeMillis(). If you convert to int, you're re-introducing the year 2038 problem. See en.wikipedia.org/wiki/Year_2038_problem#Solutions
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How to avoid warning when introducing NAs by coercion
... na = x %in% na.strings
x[na] = 0
x = as.numeric(x)
x[na] = NA_real_
x
}
as.num(c("1", "2", "X"), na.strings="X")
#[1] 1 2 NA
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Differences between Perl and PHP [closed]
...ype, of which Perl has three, and the type specifier is part of the name (called a "sigil"), so $foo is a different variable than @foo or %foo.
(related to the previous point) Perl has separate symbol table entries for scalars, arrays, hashes, code, file/directory handles and formats. Each has its o...
Query to list all stored procedures
What query can return the names of all the stored procedures in a SQL Server database
23 Answers
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How to find the type of an object in Go?
... type we have access to the full reflection capabilities
type assertions - allows grouping types, for example recognize all int32, int64, uint32, uint64 types as "int"
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How to get string objects instead of Unicode from JSON?
...unicode strings, then recurses through the entire decoded value to convert all strings to byte strings. This has a couple of undesirable effects:
A copy of the entire decoded structure gets created in memory
If your JSON object is really deeply nested (500 levels or more) then you'll hit Python's ...