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Find unique rows in numpy.array
...pe((np.void, a.dtype.itemsize * a.shape[1])))
_, idx = np.unique(b, return_index=True)
unique_a = a[idx]
>>> unique_a
array([[0, 1, 1, 1, 0, 0],
[1, 1, 1, 0, 0, 0],
[1, 1, 1, 1, 1, 0]])
EDIT
Added np.ascontiguousarray following @seberg's recommendation. This will slow the ...
MySQL search and replace some text in a field
...omitting the WHERE clause altogether is slowest, even if the column is not indexed.
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How can I set the value of a DropDownList using jQuery?
...
If you working with index you can set the selected index directly with .attr():
$("#mydropdownlist").attr('selectedIndex', 0);
This will set it to the first value in the droplist.
Edit:
The way I did it above used to work. But it seems like ...
How to COUNT rows within EntityFramework without loading contents?
...ce SQL Server really can't do anything but do a full table scan (clustered index scan).
Sometimes, it's good enough to know an approximate number of rows from the database, and in such a case, a statement like this might suffice:
SELECT
SUM(used_page_count) * 8 AS SizeKB,
SUM(row_count) ...
Postgres NOT in array
...
Note that the ANY/ALL operators will not work with array indexes. If indexes are in mind:
SELECT COUNT(*) FROM "messages" WHERE 3 && recipient_ids
and the negative:
SELECT COUNT(*) FROM "messages" WHERE NOT (3 && recipient_ids)
An index can then be created lik...
How to programmatically show next view in ViewPager?
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As blessenm answered viewpager.setCurrentItem(int index) is the way to go.
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Array vs. Object efficiency in JavaScript
...sically an array with holes in it, because every array does have continous indexing. It's slower than arrays without holes. But iterating manually through the array is even slower (mostly).
This is an object:
var a3 = {};
a3[29938] = "a";
a3[32994] = "b";
Here is a performance test of three poss...
Best practice for embedding arbitrary JSON in the DOM?
... place to put it ? head or body, top or bottom ?
– challet
Mar 20 '17 at 15:32
1
Unfortunately, i...
How do you merge two Git repositories?
...ngly simple.
(1) In A,
PREFIX=projectA #adjust this
git filter-branch --index-filter '
git ls-files -s |
sed "s,\t,&'"$PREFIX"'/," |
GIT_INDEX_FILE=$GIT_INDEX_FILE.new git update-index --index-info &&
mv $GIT_INDEX_FILE.new $GIT_INDEX_FILE
' HEAD
Note: This rewrites ...
Fast way of finding lines in one file that are not in another?
... # preserve whitespace
(NR==FNR) { ll1[FNR]=$0; nl1=FNR; } # file1, index by lineno
(NR!=FNR) { ss2[$0]++; } # file2, index by string
END {
for (ll=1; ll<=nl1; ll++) if (!(ll1[ll] in ss2)) print ll1[ll]
}
This stores the entire contents of file1 line by line in a line-...