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Contains method for a slice
...st, but is trivial to write:
func contains(s []int, e int) bool {
for _, a := range s {
if a == e {
return true
}
}
return false
}
You can use a map if that lookup is an important part of your code, but maps have cost too.
...
lenses, fclabels, data-accessor - which library for structure access and mutation is better
... a -> a)
providing two functions: a getter, and a setter
get (Lens g _) = g
put (Lens _ s) = s
subject to three laws:
First, that if you put something, you can get it back out
get l (put l b a) = b
Second that getting and then setting doesn't change the answer
put l (get l a) a = a
A...
How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?
...cessary instead of DateTime. So use Time.strptime("1318996912345",'%Q').to_f and you will see the milliseconds preserved, while DateTime.strptime("1318996912345",'%Q').to_f does not preserve it.
– skensell
Feb 22 '17 at 15:20
...
Print PHP Call Stack
...
If you want to generate a backtrace, you are looking for debug_backtrace and/or debug_print_backtrace.
The first one will, for instance, get you an array like this one (quoting the manual) :
array(2) {
[0]=>
array(4) {
["file"] => string(10) "/tmp/a.php"
["line"] => ...
Convert tuple to list and back
...
List to Tuple and back can be done as below
import ast, sys
input_str = sys.stdin.read()
input_tuple = ast.literal_eval(input_str)
l = list(input_tuple)
l.append('Python')
#print(l)
tuple_2 = tuple(l)
# Make sure to name the final tuple 'tuple_2'
print(tuple_2)
...
How to get the last N records in mongodb?
...d -1 will sort descending (newest to oldest.)
If you use the auto created _id field it has a date embedded in it ... so you can use that to order by ...
db.foo.find().sort({_id:1});
That will return back all your documents sorted from oldest to newest.
Natural Order
You can also use a Natura...
How does Dijkstra's Algorithm and A-Star compare?
...stance(int dist[], bool sptSet[])
{
// Initialize min value
int min = INT_MAX, min_index;
for (int v = 0; v < V; v++)
if (sptSet[v] == false && dist[v] <= min)
min = dist[v], min_index = v;
return min_index;
}
int printSolution(int dist[], int n)
{
printf("Vertex ...
get list from pandas dataframe column
...hon list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataFrame:\n{df}\n")
print(f"column types:\n{df.dtyp...
What are best practices for multi-language database design? [closed]
...relational table, so you get two tables, meaning (id) and word (id, meaning_id), the id in the word table represents the word id, the id in the meaning represents the meaning that is universal.
– Timo Huovinen
Sep 17 '18 at 19:27
...
Setting WPF image source in code
...packUri = "pack://application:,,,/AssemblyName;component/Images/icon.png";
_image.Source = new ImageSourceConverter().ConvertFromString(packUri) as ImageSource;
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