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Difference between Fact table and Dimension table?
...ble as the case with the fact table which always has a dimension table (or more) as a parent. Also, fact tables may be aggregated, whereas Dimension tables are not aggregated. Another reason is that fact tables are not supposed to be updated in place whereas Dimension tables could be updated in plac...
Should I use a data.frame or a matrix?
...he arguments of these functions determine the choice.
Also:
Matrices are more memory efficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are mor...
What are some (concrete) use-cases for metaclasses?
...ractive plotting wrapper and an offscreen plotting wrapper, I found it was more efficient to do this via metaclasses, wrapping the appropriate methods, than to do something like:
class PlottingInteractive:
add_slice = wrap_pylab_newplot(add_slice)
This method doesn't keep up with API changes ...
Generate a random point within a circle (uniformly)
...here. That gives a direction. Now use random()+random()+random() with some more complex folding (ie. a 6-way fold of an infinitesimally thin parallelepiped to a terahedron). Not convinced this is a good method though.
– sigfpe
May 4 '11 at 17:52
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Why avoid increment (“++”) and decrement (“--”) operators in JavaScript?
...'d be needlessly creating a temporary object. I find the postfix operator more aesthetically pleasing though.
– mc0e
Jan 11 '14 at 8:22
...
C++: const reference, before vs after type-specifier
...standard.
Due to the above factors, I think const T&/const T* have way more inertia than T const&/T const*. const T&/const T* empirically seem way more common to me than T const&/T const* in all of the C++ and C code that I've seen. I think following common practices is more readabl...
When to use RDLC over RDL reports?
...cessingMode.Remote'.
You can set parameters a user can see and use to gain more flexibility.
You can configure parts of a report to be used for connection strings as 'Data Sources' as well as a sql query, xml, or other datasets as a 'Dataset'. These parts and others can be stored and configured to ...
Should I use multiplication or division?
... faster to multiply than to divide, but as you get closer to the CPU using more advanced VMs or JITs, the advantage disappears. It's quite possible that a future Python VM would make it irrelevant
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How to use ADB Shell when Multiple Devices are connected? Fails with “error: more than one device an
...lator use adb -e shell or adb emu <command>. They'll fail if there's more than one emulator going and you'll have to fall back to -s
– Corey Ogburn
Jun 3 '16 at 20:23
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Why is good UI design so hard for some Developers? [closed]
...nd data layers? Is there something we can do to retrain our brain to be more effective at designing pleasing and useful presentation layers?
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