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Filter rows which contain a certain string
...provided the original data, I will add a toy example using the mtcars data set. Imagine you are only interested in cars produced by Mazda or Toyota.
mtcars$type <- rownames(mtcars)
dplyr::filter(mtcars, grepl('Toyota|Mazda', type))
mpg cyl disp hp drat wt qsec vs am gear carb ...
Selecting empty text input using jQuery
How do I identify empty textboxes using jQuery? I would like to do it using selectors if it is at all possible. Also, I must select on id since in the real code where I want to use this I don't want to select all text inputs.
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How do I access this object property with an illegal name?
...ar_dump($x);
So, $object->{'todo-list'} is the sub-object. If you can set it like that, then you can also read it the same way:
echo $x->{'todo-list'};
Another possibility:
$todolist = 'todo-list';
echo $x->$todolist;
If you wanted to convert it to an array, which can be a little more e...
How to style the option of an html “select” element?
...nswer your question here:
Except for background-color and color, style settings applied through the style object for the option element are ignored.
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Get the cartesian product of a series of lists?
How can I get the Cartesian product (every possible combination of values) from a group of lists?
13 Answers
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How to use MySQLdb with Python and Django in OSX 10.6?
....6 users, but I haven't been able to find a solution that works. Here's my setup:
23 Answers
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How do I use a Boolean in Python?
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empty sequences (list, tuple, string)
empty mapping types (dictionary, set, etc)
custom classes that implement __bool__ or __len__ method that returns False or 0.
every class in python has truth values defined by a special instance method:
__bool__(self) OR
__len__
When you call bool(x) ...
How to filter Android logcat by application? [duplicate]
...yManager:I MyApp:D *:S
The final element in the above expression, *:S, sets the priority level for all tags to "silent", thus ensuring only log messages with "View" and "MyApp" are displayed.
V — Verbose (lowest priority)
D — Debug
I — Info
W — Warning
E — Error
F — Fatal
S — Si...
MD5 algorithm in Objective-C
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md5 is available on the iPhone and can be added as an addition for ie NSString and NSData like below.
MyAdditions.h
@interface NSString (MyAdditions)
- (NSString *)md5;
@end
@interface NSData (MyAdditions)
- (NSString*)md5;
@end
MyAdditions.m
#import "MyAdditions.h"
#import <Com...
Detect changed input text box
... but for some reason it's not working... I get no console errors. When I set a breakpoint in the browser at the change() function it never hits it.
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