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Remove NA values from a vector
... { x[!is.na(x)] }) 66.8 75.9 130.5643 86.2 131.80 541125.5 1e+06 a
purrr::map(airquality, na.omit) 95.7 107.4 185.5108 129.3 190.50 534795.5 1e+06 b
purrr::map(airquality, ~purrr::discard(.x, .p = is.na)) 3391.7 3648.6 5615.8965 4079.7 6486.45 1121...
Diff output from two programs without temporary files
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answered Sep 26 '10 at 23:06
John KugelmanJohn Kugelman
292k6262 gold badges455455 silver badges506506 bronze badges
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PHP Pass variable to next page
...n cookies. More secure, but not completely secure.
Session:
//On page 1
$_SESSION['varname'] = $var_value;
//On page 2
$var_value = $_SESSION['varname'];
Remember to run the session_start(); statement on both these pages before you try to access the $_SESSION array, and also before any output i...
Javascript replace with reference to matched group?
I have a string, such as hello _there_ . I'd like to replace the two underscores with <div> and </div> respectively, using JavaScript . The output would (therefore) look like hello <div>there</div> . The string might contain multiple pairs of underscores.
...
Repeat string to certain length
...
def repeat_to_length(string_to_expand, length):
return (string_to_expand * ((length/len(string_to_expand))+1))[:length]
For python3:
def repeat_to_length(string_to_expand, length):
return (string_to_expand * (int(length/len(s...
What's the difference between django OneToOneField and ForeignKey?
...)
>>> e2 = Engine2.objects.get(name='Wankel')
>>> e2.car2_set.all()
[<Car2: Mazda>]
Model Code
from django.db import models
class Engine(models.Model):
name = models.CharField(max_length=25)
def __unicode__(self):
return self.name
class Car(models.Model)...
Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
... your table(s) has by using this query:
SELECT
col.name, col.collation_name
FROM
sys.columns col
WHERE
object_id = OBJECT_ID('YourTableName')
Collations are needed and used when ordering and comparing strings. It's generally a good idea to have a single, unique collation used through...
What is the python keyword “with” used for? [duplicate]
...t in an object that supports the context management protocol (that is, has __enter__() and __exit__() methods).
Update fixed VB callout per Scott Wisniewski's comment. I was indeed confusing with with using.
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One-liner to check whether an iterator yields at least one element?
...In case the iterator yields something false-ish you can write any(True for _ in iterator).
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performSelector may cause a leak because its selector is unknown
... should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller methodForSelector:selector];
void (*func)(id, SEL) = (void *)imp;
func(_controller, selector);
Or more tersely (though hard...