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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 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...
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...
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
7,90699 gold badges2626 silver badges4343 bronze badges
answered Oct 12 '11 at 5:32
Dirk EddelbuettelDir...
What optimizations can GHC be expected to perform reliably?
...
+150
This GHC Trac page also explains the passes fairly well. This page explains the optimization ordering, though, like the majority of th...
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 .
...
Logical operators for boolean indexing in Pandas
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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 ...
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...
How to show all shared libraries used by executables in Linux?
...-e '/^[^\t]/ d' \
| sed -e 's/\t//' \
| sed -e 's/.*=..//' \
| sed -e 's/ (0.*)//' \
| sort \
| uniq -c \
| sort -n
Change "/bin" above to "/" to search all directories.
Output (for just the /bin directory) will look something like this:
1 /lib64/libexpat.so.0
1 /lib64/libgcc_s.so.1
1 /lib...