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Quickest way to convert a base 10 number to any base in .NET?
... methods are faster than any others posted so far. I was able to convert 1,000,000 numbers from and to base 36 in under 400ms in a single core machine.
Example below is for base 62. Change the BaseChars array to convert from and to any other base.
private static readonly char[] BaseChars =
...
Does MS SQL Server's “between” include the range boundaries?
...second, -3, '20160701')
i.e.
where myDateTime between '20160601 00:00:00.000' and '20160630 23:59:59.997'
datetime2 and datetimeoffset
Subtracting 3 ms from a date will leave you vulnerable to missing rows from the 3 ms window. The correct solution is also the simplest one:
where myDateTime >...
How to map and remove nil values in Ruby
...nchmarks against some of the earlier approaches to this problem:
N = 1_00_000
enum = 1.upto(1_000)
Benchmark.bmbm do |x|
x.report("select + map") { N.times { enum.select { |i| i.even? }.map{|i| i + 1} } }
x.report("map + compact") { N.times { enum.map { |i| i + 1 if i.even? }.compact } }
x.r...
How to display pandas DataFrame of floats using a format string for columns?
...mary:
df = pd.DataFrame({'money': [100.456, 200.789], 'share': ['100,000', '200,000']})
print(df)
print(df.to_string(formatters={'money': '${:,.2f}'.format}))
for col_name in ('share',):
df[col_name] = df[col_name].map(lambda p: int(p.replace(',', '')))
print(df)
""...
outline on only one border
... block;
padding: 2px 0;
line-height: 1px;
border-top: 1px dashed #000;
}
.element p {
padding: 0 10px;
}
<div class="element">
<p>Some content comes here...</p>
</div>
(Or see external demo.)
All sizes and colors are just placeholders, you can cha...
PDOException SQLSTATE[HY000] [2002] No such file or directory
...was working with models and DB I got the error:
[PDOException]
SQLSTATE[HY000] [2002] No such file or directory
The reason I found is just because PHP and MySQL can't get connected themselves.
To get this problem fixed, I follow the next steps:
Open a terminal and connect to the mysql with:
my...
Speed up the loop operation in R
...
So how better is it?
I run each function for data.frame with nrow from 1,000 to 10,000 by 1,000 and measure time with system.time
X <- as.data.frame(matrix(sample(1:10, n*9, TRUE), n, 9))
system.time(dayloop2(X))
Result is
You can see that your version depends exponentially from nrow(X). ...
How to extract numbers from a string and get an array of ints?
... This method detects digits but does not detect formated numbers, e.g. 2,000. For such use -?\\d+,?\\d+|-?\\d+
– Mugoma J. Okomba
Mar 9 '16 at 12:25
...
Replace non-ASCII characters with a single space
...ASCII replacement methods."""
import re
from timeit import timeit
# 10_000 is typical in the project that I'm working on and most of the text
# is going to be non-ASCII.
text = 'Æ' * 10_000
print(timeit(
"""
result = ''.join([c if ord(c) < 128 else '?' for c in text])
""",
numb...
What is the recommended batch size for SqlBulkCopy?
..., about 30 bytes per row.
Given this scenario, I found a batch size of 5,000 to be the best compromise of speed and memory consumption. I started with 500 and experimented with larger. I found 5000 to be 2.5x faster, on average, than 500. Inserting the 6 million rows takes about 30 seconds with a ...