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leading zeros in rails
...eld, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
...
Is it possible to declare two variables of different types in a for loop?
...tax has been supported in gcc and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above will give you:
int i set to 1
double f set...
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...
Make xargs execute the command once for each line of input
...
405
The following will only work if you do not have spaces in your input:
xargs -L 1
xargs --max-l...
Perl build, unit testing, code coverage: A complete working example
...
105
It took me a while and it also took me taking small snippets from a number of different sources...
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 configure PostgreSQL to accept all incoming connections
...
Just use 0.0.0.0/0.
host all all 0.0.0.0/0 md5
Make sure the listen_addresses in postgresql.conf (or ALTER SYSTEM SET) allows incoming connections on all available IP interfaces.
listen_addres...
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....
Replacing NAs with latest non-NA value
...
divibisan
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answered Oct 12 '11 at 5:32
Dirk EddelbuettelDir...
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...