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ERROR 2003 (HY000): Can't connect to MySQL server on '127.0.0.1' (111)
...abled):
run the command vim /etc/mysql/my.cnf
comment bind-address = 127.0.0.1 using the # symbol
restart your mysql server once.
Update
In Step 1, if you cannot find bind-address in the my.cnf file, look for it in /etc/mysql/mysql.conf.d/mysqld.cnf file.
Update in case of MySQL replication en...
How to map atan2() to degrees 0-360
atan2(y, x) has that discontinuity at 180° where it switches to -180°..0° going clockwise.
15 Answers
...
What does the “|” (single pipe) do in JavaScript?
Why does 0.5 | 0 return zero, but any integer (including negative) returns the input integer? What does the single pipe ("|") do?
...
Delete first character of a string in Javascript
...ant to delete the first character of a string, if the first character is a 0. The 0 can be there more than once.
14 Answer...
What is the best way to convert seconds into (Hour:Minutes:Seconds:Milliseconds) time?
...
For .Net <= 4.0 Use the TimeSpan class.
TimeSpan t = TimeSpan.FromSeconds( secs );
string answer = string.Format("{0:D2}h:{1:D2}m:{2:D2}s:{3:D3}ms",
t.Hours,
t.Minutes,
t.Seconds,
...
What are the advantages of using nullptr?
... handle nullptr argument!!!
1. In C++, NULL is defined as #define NULL 0, so it is basically int, that is why f(int) is called.
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Sample random rows in dataframe
...
460
First make some data:
> df = data.frame(matrix(rnorm(20), nrow=10))
> df
X1 ...
How do I get bit-by-bit data from an integer value in C?
...wanted){
int *bits = malloc(sizeof(int) * bitswanted);
int k;
for(k=0; k<bitswanted; k++){
int mask = 1 << k;
int masked_n = n & mask;
int thebit = masked_n >> k;
bits[k] = thebit;
}
return bits;
}
int main(){
int n=7;
int bitswanted = 5;
int...
How to truncate the time on a DateTime object in Python?
...
390
I think this is what you're looking for...
>>> import datetime
>>> dt = datet...
Pandas groupby: How to get a union of strings
..._csv(StringIO(data),sep='\s+')
In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When...