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How to format a Java string with leading zero?
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In case you have to do it without the help of a library:
("00000000" + "Apple").substring("Apple".length())
(Works, as long as your String isn't longer than 8 chars.)
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impro...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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640
Difference between == and ===
The difference between the loosely == equal operator and the stri...
How to strip HTML tags from a string in SQL Server?
I've got data in SQL Server 2005 that contains HTML tags and I'd like to strip all that out, leaving just the text between the tags. Ideally also replacing things like < with < , etc.
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Change column type from string to float in Pandas
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+200
You have four main options for converting types in pandas:
to_numeric() - provides functionality to safely convert non-numeric types...
Drawing an image from a data URL to a canvas
...t('2d');
var img = new Image;
img.onload = function(){
ctx.drawImage(img,0,0); // Or at whatever offset you like
};
img.src = strDataURI;
Edit: I previously suggested in this space that it might not be necessary to use the onload handler when a data URI is involved. Based on experimental tests f...
Group by multiple columns in dplyr, using string vector input
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data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %>%...
Bitwise operation and usage
...bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its inputs are 1, otherwise it's 0.
NOT is 1 only if its input is 0, otherwise it's 0.
These can often be best shown as truth ...
Fastest way to list all primes below N
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+100
Warning: timeit results may vary due to differences in hardware or
version of Python.
Below is a script which compares a number of...
Best way to combine two or more byte arrays in C#
...he suggested methods in a loop executed 1 million times using 3 arrays of 10 bytes each. Here are the results:
New Byte Array using System.Array.Copy - 0.2187556 seconds
New Byte Array using System.Buffer.BlockCopy - 0.1406286 seconds
IEnumerable<byte> using C# yield operator - 0....
Getting the first character of a string with $str[0]
I want to get the first letter of a string and I've noticed that $str[0] works great. I am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right –...