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Which iOS app version/build number(s) MUST be incremented upon App Store release?
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In Python, how do you convert a `datetime` object to seconds?
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typecast string to integer - Postgres
...lesced field such as, for example:-
SELECT CAST(coalesce(<column>, '0') AS integer) as new_field
from <table>
where CAST(coalesce(<column>, '0') AS integer) >= 10;
share
|
im...
How can I create a correlation matrix in R?
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104
An example,
d &lt- data.frame(x1=rnorm(10),
x2=rnorm(10),
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Test whether string is a valid integer
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[[ $var =~ ^-?[0-9]+$ ]]
The ^ indicates the beginning of the input pattern
The - is a literal "-"
The ? means "0 or 1 of the preceding (-)"
The + means "1 or more of the preceding ([0-9])"
The $ indicates the end of the input pattern
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remove None value from a list without removing the 0 value
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How to read the content of a file to a string in C?
...-codes for fseek, ftell and fread. (omitted for clarity).
char * buffer = 0;
long length;
FILE * f = fopen (filename, "rb");
if (f)
{
fseek (f, 0, SEEK_END);
length = ftell (f);
fseek (f, 0, SEEK_SET);
buffer = malloc (length);
if (buffer)
{
fread (buffer, 1, length, f);
}
fclo...
How to map and remove nil values in Ruby
...ct it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simply:
items.filter_map { |x| process_x url }
"Ruby 2.7 adds Enumerable#filter_map" is a good read on t...
What is the Difference Between read() and recv() , and Between send() and write()?
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130
The difference is that recv()/send() work only on socket descriptors and let you specify certain...
How to get the unix timestamp in C#
...estamp in C# by using DateTime.UtcNow and subtracting the epoch time of 1970-01-01.
e.g.
Int32 unixTimestamp = (Int32)(DateTime.UtcNow.Subtract(new DateTime(1970, 1, 1))).TotalSeconds;
DateTime.UtcNow can be replaced with any DateTime object that you would like to get the unix timestamp for.
Th...