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Filter rows which contain a certain string
...n easily extend to more than one column.
Below also a solution with filter_all in order to find the string in any column,
using diamonds as example, looking for the string "V"
library(tidyverse)
String in only one column
# for only one column... extendable to more than one creating a column list in...
How to elegantly deal with timezones
...t is that inside the DB, date/times are stored in UTC. When on the server, all date/times should be dealt with in UTC. However, I see three problems that I'm trying to overcome:
...
WordPress asking for my FTP credentials to install plugins
I installed a WordPress blog in my local system. But when I try to add plugins from admin it asks for FTP access. What do I need to configure for WordPress to be able to upload without FTP?
...
What is the relationship between UIView's setNeedsLayout, layoutIfNeeded and layoutSubviews?
...fNeeded and layoutSubviews methods? And an example implementation where all three would be used. Thanks.
2 Answers
...
Property getters and setters
...g to backup the computed property. Try this:
class Point {
private var _x: Int = 0 // _x -> backingX
var x: Int {
set { _x = 2 * newValue }
get { return _x / 2 }
}
}
Specifically, in the Swift REPL:
15> var pt = Point()
pt: Point = {
_x = 0
}
16> pt.x = 10...
iOS JavaScript bridge
...t's something simple enough that you might give it a try yourself. I personally did exactly this when I needed to do that. You might also create a simple library that suits your needs.
1. Execute JS methods from Objective-C
This is really just one line of code.
NSString *returnvalue = [webView st...
Unique fields that allow nulls in Django
...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms.ModelForm):
class Meta:
model = Foo
def clean_bar(self):
return self.cleaned_data['bar'] or None
class FooAdmin(admin.ModelAdmin...
Separating class code into a header and cpp file
...
So this means that all files that include your header file will "see" the private members. If for example you want to publish a lib and its header, you have to show the private members of the class?
– Gauthier
...
iPhone viewWillAppear not firing
... my navigation controller's delegate and still the method was not getting called. Anyway, I set it and then I used the methods you mention above. Thanks.
– Dimitris
Mar 29 '10 at 12:53
...
Substitute multiple whitespace with single whitespace in Python [duplicate]
...ce characters that are combined.
To match unicode whitespace:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"\s+")
my_str = _RE_COMBINE_WHITESPACE.sub(" ", my_str).strip()
To match ASCII whitespace only:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"(?a:\s+)")
_RE_STRIP_WHITESPACE = re.co...