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Correct way to convert size in bytes to KB, MB, GB in JavaScript
...bytes) {
var sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB'];
if (bytes == 0) return '0 Byte';
var i = parseInt(Math.floor(Math.log(bytes) / Math.log(1024)));
return Math.round(bytes / Math.pow(1024, i), 2) + ' ' + sizes[i];
}
Note : This is original code, Please use fixed version below. Ali...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
...ications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
I spent several days to solve this problem. I have tested many approaches that have been mentioned in different web sites, but non of them worked....
C++: Rounding up to the nearest multiple of a number
...ger math.
int roundUp(int numToRound, int multiple)
{
if (multiple == 0)
return numToRound;
int remainder = numToRound % multiple;
if (remainder == 0)
return numToRound;
return numToRound + multiple - remainder;
}
Edit: Here's a version that works with negative n...
How do you create a yes/no boolean field in SQL server?
...
The equivalent is a BIT field.
In SQL you use 0 and 1 to set a bit field (just as a yes/no field in Access). In Management Studio it displays as a false/true value (at least in recent versions).
When accessing the database through ASP.NET it will expose the field as a b...
Get a random boolean in python?
...ter
$ python -m timeit -s "import random" "random.choice([True, False])"
1000000 loops, best of 3: 0.904 usec per loop
$ python -m timeit -s "import random" "random.choice((True, False))"
1000000 loops, best of 3: 0.846 usec per loop
$ python -m timeit -s "import random" "random.getrandbits(1)"
10...
Remove duplicated rows using dplyr
...r below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data fr...
How to create an array containing 1…N
...
409
If I get what you are after, you want an array of numbers 1..n that you can later loop through....
How to format numbers by prepending 0 to single-digit numbers?
I want to format a number to have two digits. The problem is caused when 0 – 9 is passed, so I need it to be formatted to 00 – 09 .
...
In C++, is it still bad practice to return a vector from a function?
...arrays—in many programming languages. Is this style now acceptable in C++0x if the class has a move constructor, or do C++ programmers consider it weird/ugly/abomination?
...
Logical operators for boolean indexing in Pandas
...
When you say
(a['x']==1) and (a['y']==10)
You are implicitly asking Python to convert (a['x']==1) and (a['y']==10) to boolean values.
NumPy arrays (of length greater than 1) and Pandas objects such as Series do not have a boolean value -- in other words, they ...