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parseInt vs unary plus, when to use which?
..., here are a few differences I know of:
An empty string "" evaluates to a 0, while parseInt evaluates it to NaN. IMO, a blank string should be a NaN.
+'' === 0; //true
isNaN(parseInt('',10)); //true
The unary + acts more like parseFloat since it also accepts decimals.
parseInt on...
What is the difference between libsqlite3.dylib and libsqlite3.0.dylib?
...rial is linking the SQLite3 framework. The tutorial calls for libsqlite3.0.dylib but I noticed another one libsqlite3.dylib. Is the latter just a symlink to the latest v3 library like the convention for package managers on UNIX or is there a difference?
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#define macro for debug printing in C?
... \
do { if (DEBUG) fprintf(stderr, fmt, __VA_ARGS__); } while (0)
It assumes you are using C99 (the variable argument list notation is not supported in earlier versions). The do { ... } while (0) idiom ensures that the code acts like a statement (function call). The unconditional use...
How to create an array containing 1…N
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409
If I get what you are after, you want an array of numbers 1..n that you can later loop through....
How to toggle a value in Python
What is the most efficient way to toggle between 0 and 1 ?
17 Answers
17
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Reordering arrays
... would be:
Array.prototype.move = function (from, to) {
this.splice(to, 0, this.splice(from, 1)[0]);
};
Then just use:
var ar = [1,2,3,4,5];
ar.move(0,3);
alert(ar) // 2,3,4,1,5
Diagram:
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Append value to empty vector in R?
...et.seed(21)
values <- sample(letters, 1e4, TRUE)
vector <- character(0)
# slow
system.time( for (i in 1:length(values)) vector[i] <- values[i] )
# user system elapsed
# 0.340 0.000 0.343
vector <- character(length(values))
# fast(er)
system.time( for (i in 1:length(values)) vec...
Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...e BIT datatype to represent boolean data. A BIT field's value is either 1, 0, or null.
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Why does 2 mod 4 = 2?
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edited Aug 29 '09 at 17:33
Joe Phillips
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