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Time complexity of Sieve of Eratosthenes algorithm
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4 Answers
4
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Select statement to find duplicates on certain fields
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840
To get the list of fields for which there are multiple records, you can use..
select field1,fie...
How to remove last n characters from every element in the R vector
..._bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
share
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What is IP address '::1'?
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BradBrad
140k3737 gold badges282282 silver badges452452 bronze badges
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jQuery map vs. each
...u can potentially waste a lot of memory.
For example:
var items = [1,2,3,4];
$.each(items, function() {
alert('this is ' + this);
});
var newItems = $.map(items, function(i) {
return i + 1;
});
// newItems is [2,3,4,5]
You can also use the map function to remove an item from an array. For...
Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...t how the + operator behaves in general also.
So, here it goes.
Excluding E4X and implementation-specific stuff, Javascript (as of ES5) has 6 built-in data types:
Undefined
Null
Boolean
Number
String
Object
Note that although typeof somewhat confusingly returns object for Null and function for cal...
How to get all subsets of a set? (powerset)
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edited Jun 9 '19 at 17:49
Ran Feldesh
53955 silver badges1313 bronze badges
answered Sep 26 '09 at 22...
Small Haskell program compiled with GHC into huge binary
...'s see what's going on, try
$ du -hs A
13M A
$ file A
A: ELF 64-bit LSB executable, x86-64, version 1 (SYSV),
dynamically linked (uses shared libs), for GNU/Linux 2.6.27, not stripped
$ ldd A
linux-vdso.so.1 => (0x00007fff1b9ff000)
libXrandr.so.2 => /usr/lib/libX...
Is it possible to for SQL Output clause to return a column not being inserted?
...ld1 INT, Field2 INT)
INSERT INTO Practice VALUES (1, 1), (2, 2), (3, 3), (4, 4)
MERGE INTO ReportOption r USING Practice p ON 1 = 0
WHEN NOT MATCHED THEN
INSERT (field1, field2)
VALUES (p.Field1, p.Field2)
OUTPUT p.PracticeId, inserted.ReportOptionId, inserted.Field1, inserted.Field2
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Selecting data frame rows based on partial string match in a column
...), ]
mpg cyl disp hp drat wt qsec vs am gear carb
# Merc 240D 24.4 4 146.7 62 3.69 3.19 20.0 1 0 4 2
# Merc 230 22.8 4 140.8 95 3.92 3.15 22.9 1 0 4 2
# Merc 280 19.2 6 167.6 123 3.92 3.44 18.3 1 0 4 4
# Merc 280C 17.8 6 167.6 123 3.92 3.4...