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Mean per group in a data.frame [duplicate]
... the many ways to specify the variables to act on. Here, vars(-Month) says all variables except Month.
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Log all queries in mysql
..._file=/usr/log/general.log
in your my.cnf / my.ini file
Ubuntu/Debian: /etc/mysql/my.cnf
Windows: c:\ProgramData\MySQL\MySQL Server 5.x
wamp: c:\wamp\bin\mysql\mysqlx.y.z\my.ini
xampp: c:\xampp\mysql\bin\my.ini.
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Database development mistakes made by application developers [closed]
...es to deal with problems that are trivial in langues like Java, C#, Delphi etc.
This lack of understanding manifests itself in a few ways.
Inappropriately imposing too much procedural or imperative logic on the databse.
Inappropriate or excessive use of cursors. Especially when a single query wou...
What is the difference between exit(0) and exit(1) in C?
...ccessful program termination & it is fully portable, While
exit(1) (usually) indicates unsucessful termination. However, it's usage is non-portable.
Note that the C standard defines EXIT_SUCCESS and EXIT_FAILURE to return termination status from a C program.
0 and EXIT_SUCCESS are the values s...
How to discover number of *logical* cores on Mac OS X?
...et "error: "hw.ncpu" is an unknown key". There is no cpu related entry in /etc/sysctl.conf as well. Frozen Flame's answer worked.
– TheGT
Oct 5 '16 at 23:39
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How to install the Raspberry Pi cross compiler on my Linux host machine?
...-gcc -v. You should get something like this:
Using built-in specs.
COLLECT_GCC=arm-linux-gnueabihf-gcc
COLLECT_LTO_WRAPPER=/home/tudhalyas/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/../libexec/gcc/arm-linux-gnueabihf/4.7.2/lto-wrapper
Target: arm-linux-gnueabihf
Confi...
How to add pandas data to an existing csv file?
...opening and closing your file multiple times, or logging data, statistics, etc.
from contextlib import contextmanager
import pandas as pd
@contextmanager
def open_file(path, mode):
file_to=open(path,mode)
yield file_to
file_to.close()
##later
saved_df=pd.DataFrame(data)
with open_f...
Knight's Shortest Path on Chessboard
...
You have a graph here, where all available moves are connected (value=1), and unavailable moves are disconnected (value=0), the sparse matrix would be like:
(a1,b3)=1,
(a1,c2)=1,
.....
And the shortest path of two points in a graph can be found usin...
C# Class naming convention: Is it BaseClass or ClassBase or AbstractClass
...d many Base* classes in the framework. CollectionBase, DictionaryBase .... etc
– Chad Grant
May 5 '09 at 21:53
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How to make part of the text Bold in android at runtime?
...ion has many string elements like name , experience , date of joining , etc. I just want to make name bold. All the string elements will be in a single TextView .
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