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Floating point vs integer calculations on modern hardware
...r math. The Alpha processor had a FP divide instruction but not an integer one, so integer division had to be done in software.
– Gabe
Mar 31 '10 at 4:49
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How do I (or can I) SELECT DISTINCT on multiple columns?
...ND s1.ctid <> s.ctid
Every table should have a primary key. Add one if you didn't have one, yet. I suggest a serial or an IDENTITY column in Postgres 10+.
Related:
In-order sequence generation
Auto increment table column
How is this faster?
The subquery in the EXISTS anti-semi-join ...
Which version of Perl should I use on Windows? [closed]
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Strawberry Perl is just getting better and better. One problem I've repeatedly had with ActiveState is that my modules sometimes fail to install because I need an upgrade to a core module, but they won't allow that. Thus, everybody who doesn't use Windows can use my code, bu...
Leaflet - How to find existing markers, and delete markers?
...er that way, because each time, the var marker is erased by the latest. So one way to go is to create a global array of marker, and you add your marker in the global array.
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Finding the type of an object in C++
...c_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime check to ensure the validity of the cast.
If you attempt to cast to pointer to a type that is not a type of actual object, the result of the cast will be NULL. If...
Google Maps API v3: Can I setZoom after fitBounds?
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I solved a similar problem in one of my apps. I was a little confused by your description of the problem, but I think you have the same goal I had...
In my app I wanted to plot a one or more markers and ensure the map was showing them all. The problem ...
Python Create unix timestamp five minutes in the future
...'s comment enough. If you're trying to get a UNIX timestamp (and therefore one in UTC), use calendar.timegm.
– Bialecki
Feb 20 '13 at 20:58
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Can I control the location of .NET user settings to avoid losing settings on application upgrade?
... answered Mar 7 '09 at 4:40
uzbonesuzbones
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How do I calculate the normal vector of a line segment?
...(x', y') = (-y, x) and (x', y') = (y, -x) seems to be right, but why would one use dx and dy here. Moreover, based on slopes, m1 * m2 = -1 for right angle lines, hence dy' = dx' * (-dx/dy) and dx' = dy' * (-dy/dx), how come in your equation normal.x = x' = -dy?
– legends2k
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How to see which plugins are making Vim slow?
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Just in case anyone else is wondering, this doesn't exist in all vim/gvim distros. Doesn't in a stock Win Gvim 7.4 over here (though it is documented in viminfo)
– thynctank
Aug 26 '14 at 16:28
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