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Can PostgreSQL index array columns?
... CREATE TABLE "Test"("Column1" int[]);
INSERT INTO "Test" VALUES ('{10, 15, 20}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because we have only 2 records for this test...
SET enable_seqscan ...
Ruby max integer
...ts (integers small enough to store in a single machine word), you can call 0.size to get the number of bytes. I would guess it should be 4 on 32-bit builds, but I can't test that right now. Also, the largest Fixnum is apparently 2**30 - 1 (or 2**62 - 1), because one bit is used to mark it as an inte...
An “and” operator for an “if” statement in Bash
...US} is empty. It would probably be better to do:
if ! [ "${STATUS}" -eq 200 ] 2> /dev/null && [ "${STRING}" != "${VALUE}" ]; then
or
if [ "${STATUS}" != 200 ] && [ "${STRING}" != "${VALUE}" ]; then
It's hard to say, since you haven't shown us exactly what is going wrong wit...
How to add item to the beginning of List?
...
Use the Insert method:
ti.Insert(0, initialItem);
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Getting image dimensions without reading the entire file
...
106
Your best bet as always is to find a well tested library. However, you said that is difficult, ...
How to print a string in fixed width?
...
EDIT 2013-12-11 - This answer is very old. It is still valid and correct, but people looking at this should prefer the new format syntax.
You can use string formatting like this:
>>> print '%5s' % 'aa'
aa
>>>...
Determining complexity for recursive functions (Big O notation)
...O notation, for each function:
int recursiveFun1(int n)
{
if (n <= 0)
return 1;
else
return 1 + recursiveFun1(n-1);
}
This function is being called recursively n times before reaching the base case so its O(n), often called linear.
int recursiveFun2(int n)
{
if (n &...
float64 with pandas to_csv
...
df.to_csv('pandasfile.csv', float_format='%.3f')
or, if you don't want 0.0001 to be rounded to zero:
df.to_csv('pandasfile.csv', float_format='%g')
will give you:
Bob,0.085
Alice,0.005
in your output file.
For an explanation of %g, see Format Specification Mini-Language.
...
How to add image to canvas
....png';
base_image.onload = function(){
context.drawImage(base_image, 0, 0);
}
}
I.e. draw the image in the onload callback of the image.
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What's the difference between echo, print, and print_r in PHP?
...s you have in your variables. Consider this test program:
$values = array(0, 0.0, false, '');
var_dump($values);
print_r ($values);
With print_r you can't tell the difference between 0 and 0.0, or false and '':
array(4) {
[0]=>
int(0)
[1]=>
float(0)
[2]=>
bool(false)
[3]=...