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How to store values from foreach loop into an array?
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Declare the $items array outside the loop and use $items[] to add items to the array:
$items = array();
foreach($group_membership as $username) {
$items[] = $username;
}
print_r($items);
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How to use the 'sweep' function
When I look at the source of R Packages, i see the function sweep used quite often.
Sometimes it's used when a simpler function would have sufficed (e.g., apply ),
other times, it's impossible to know exactly what it's is doing without
spending a fair amount of time to step through the code block...
Using the HTML5 “required” attribute for a group of checkboxes?
... required='required' ;
and the form field is empty/blank;
and the submit button is clicked;
the browsers detects that the "required" field is empty and does not submit the form; instead browser shows a hint asking the user to type text into the field.
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How to specify the location with wget?
...long form) to your command. Also note that if the directory does not exist it will get created.
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npm WARN package.json: No repository field
I installed Express.js with the following command:
11 Answers
11
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Linux: is there a read or recv from socket with timeout?
How can I try to read data from socket with timeout?
I know, select, pselect, poll, has a timeout field, but using of them disables "tcp fast-path" in tcp reno stack.
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How do I add a foreign key to an existing SQLite table?
... FOREIGN KEY (parent_id)
REFERENCES parent(id);
SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command (sqlite.org: SQL Features That SQLite Does Not Implement).
Therefore, the only way to add a foreign key in sqlite 3.6.1 is during CREATE TABLE as fol...
Temporarily disable auto_now / auto_now_add
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I've recently faced this situation while testing my application. I needed to "force" an expired timestamp. In my case I did the trick by using a queryset update. Like this:
# my model
class FooBar(models.Model):
title = models.CharField(max_lengt...
get list from pandas dataframe column
...call x.tolist() on to turn them into a Python 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:...
Python “extend” for a dictionary
What is the best way to extend a dictionary with another one while avoiding the use of a for loop? For instance:
7 Answer...