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Counting DISTINCT over multiple columns
...umn is deterministic and you are using "sane" database settings, it can be indexed and / or statistics can be created on it.
I believe a distinct count of the computed column would be equivalent to your query.
share
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Django, creating a custom 500/404 error page
... for some reason request.user appears fine in the 404 template, but not at all in the 500 template (and they are almost identical) -- posted question on this here: stackoverflow.com/questions/26043211/…
– Gravity Grave
Sep 25 '14 at 16:13
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Replace a value in a data frame based on a conditional (`if`) statement
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Short answer is:
junk$nm[junk$nm %in% "B"] <- "b"
Take a look at Index vectors in R Introduction (if you don't read it yet).
EDIT. As noticed in comments this solution works for character vectors so fail on your data.
For factor best way is to change level:
levels(junk$nm)[levels(junk...
Finding quaternion representing the rotation from one vector to another
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Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
What is the use of the %n format specifier in C?
...reak up or modify the resulting string, since the value stored is an array index into the resulting string. This application is a lot more useful, however, with sscanf, especially since functions in the scanf family don't return the number of chars processed but the number of fields.
Another really...
Disable assertions in Python
...trate each.
For the whole process
Using the -O flag (capital O) disables all assert statements in a process.
For example:
$ python -Oc "assert False"
$ python -c "assert False"
Traceback (most recent call last):
File "<string>", line 1, in <module>
AssertionError
Note that by di...
Download attachments using Java Mail
Now that I`ve downloaded all the messages, and store them to
4 Answers
4
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Circle line-segment collision detection algorithm?
... exdx + eydy - dxh - dyk ) +
ex2 + ey2 -
2exh - 2eyk + h2 + k2 - r2 = 0
Finally,
t2( _d * _d ) + 2t( _e * _d - _d * _c ) + _e * _e - 2( _e*_c ) + _c * _c - r2 = 0
*Where _d is the vector d and * is the dot product.*
And then,
t2( _d * _d ) + 2t( _d * ( _e - _c ) ) + ( _e - _c ) * ( _e - _c ) - r2 = ...
Android: How to bind spinner to custom object list?
...ass)
label.setText(values[position].getName());
// And finally return your dynamic (or custom) view for each spinner item
return label;
}
// And here is when the "chooser" is popped up
// Normally is the same view, but you can customize it if you want
@Overr...
Insert into … values ( SELECT … FROM … )
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is it Necessary that we insert into all columns of the table
– maheshmnj
Feb 24 at 7:22
1
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