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Python pandas Filtering out nan from a data selection of a column of strings
...re at least two non-NaN.
Then you could then drop where name is NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob NaN NaN
5 lob NaN NaN
[5 rows x 3 columns]
In [89]:
nms = nms.dropna(thresh=2)
In ...
What is the fastest way to compute sin and cos together?
...r than table lookups.
Edit:
Wikipedia suggests that FSINCOS was added at 387 processors, so you can hardly find a processor which doesn't support it.
Edit:
Intel's documentation states that FSINCOS is just about 5 times slower than FDIV (i.e., floating point division).
Edit:
Please note that not ...
How to set Python's default version to 3.x on OS X?
... both ~/.bash_aliases and ~/.bash_profile.
– Haymaker87
Jul 26 '16 at 15:41
43
@Haymaker87 run so...
Android Studio with Google Play Services
...ies:
dependencies {
compile 'com.google.android.gms:play-services:6.5.87'
}
And finally syncronise your project (the button to the left of the AVD manager).
Since version 6.5 you can include the complete library (very large) or just the modules that you need (Best Option). I.e if you onl...
Retrieve the commit log for a specific line in a file?
...short -u -L 155,155:git-web--browse.sh
commit 81f42f11496b9117273939c98d270af273c8a463
Author: Giuseppe Bilotta <giuseppe.bilotta@gmail.com>
web--browse: support opera, seamonkey and elinks
diff --git a/git-web--browse.sh b/git-web--browse.sh
--- a/git-web--browse.sh
+++ b/git-web--brows...
How to check if a stored procedure exists before creating it
...rocedural code anywhere you are able to run a query.
Just copy everything after AS:
BEGIN
DECLARE @myvar INT
SELECT *
FROM mytable
WHERE @myvar ...
END
This code does exactly same things a stored proc would do, but is not stored on the database side.
That's much like what ...
Why should I care about lightweight vs. annotated tags?
... is that you know who created it. Just like with commits, sometimes it's nice to know who did it. If you're a developer and you see that v1.7.4 has been tagged (declared ready) and you're not so sure, who do you talk to? The person whose name is in the annotated tag! (If you live in a distrustful wo...
What is the LD_PRELOAD trick?
... ...
libselinux.so.1 =>
/home/patric/libselinux.so.1 (0x00007fb9245d8000)
...
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Add a column with a default value to an existing table in SQL Server
...rate
a Default-Contraint with a funny Name like: DF__SomeTa__SomeC__4FB7FEF6
Optional With-Values Statement:
The WITH VALUES is only needed when your Column is Nullable
and you want the Default Value used for Existing Records.
If your Column is NOT NULL, then it will automatically use t...
Wildcards in jQuery selectors
...
niconico
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