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How to check if object (variable) is defined in R?
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64
if you are inside a function, missing() is what you want.
exchequer = function(x) {
if(mis...
Git Tag list, display commit sha1 hashes
...08cf8df08571d3 commit refs/tags/1.4.9
e25952a74bf379783944bef9c4fcc60600cb764c commit refs/tags/1.4.8
19b1c2c96a9678837f57eac86cf3d22842731510 commit refs/tags/1.4.7
7208212a55c4a56af34da781a7f730d6ddd557a1 commit refs/tags/1.4.6
62ec20337a4125496bd4f56288f3283963153194 commit refs/tags/1.4.5
Resu...
Private and protected constructor in Scala
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64
Aleksander's answer is correct, but Programming in Scala offers an additional alternative:
sea...
Pandas get topmost n records within each group
... 2 3
1 2
2 6 4
5 3
3 7 1
4 8 1
dtype: int64
There's a slight weirdness that you get the original index in there as well, but this might be really useful depending on what your original index was.
If you're not interested in it, you can do .reset_index(level=1, dr...
How can I make pandas dataframe column headers all lowercase?
... 9.572999e+05
2 Canada CAN 2003 1.40105 1.016902e+06
In [64]: df.columns = df.columns.str.lower()
In [65]: df
Out[65]:
country country isocode year xrat tcgdp
0 Canada CAN 2001 1.54876 9.249094e+05
1 Canada CAN 2002 1.56932 9.572999e...
Find the files existing in one directory but not in the other [closed]
...2/tmp/.kconfig-flavor_maxim2 added
DIR dir2/tools/tools/LiveSuit_For_Linux64 added
Or if you want to see only files from the first directory:
user@laptop:~$ python3 compare_dirs.py dir2/ dir1/ | grep dir1
DIR dir1/out/flavor-domino added
DIR dir1/target/vendor/flavor-domino added
FILE dir1/tm...
Do a “git export” (like “svn export”)?
... etarion
15.1k33 gold badges3939 silver badges6464 bronze badges
answered Oct 2 '08 at 3:03
Greg HewgillGreg Hewgill
783k167...
List of standard lengths for database fields
...@ian-nelson Email length according to RFC 3696: That limit is a maximum of 64 characters (octets) in the "local part" (before the "@") and a maximum of 255 characters (octets) in the domain part (after the "@") for a total length of 320 characters. Systems that handle email should be prepa...
Is there a way to run Bash scripts on Windows? [closed]
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colinux doesn't work on 64-bit (yet)
– hexicle
Aug 19 '13 at 21:14
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HTTP headers in Websockets client API
...ve results in the following header with the string "username:password" base64 encoded:
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=
I have tested basic auth in Chrome 55 and Firefox 50 and verified that the basic auth info is indeed negotiated with the server (this may not work in Safari).
Than...