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What are the “standard unambiguous date” formats for string-to-date conversion in R?
...here a better solution than needing to specify the format?
Yes, there is now (ie in late 2016), thanks to anytime::anydate from the anytime package.
See the following for some examples from above:
R> anydate(c("01 Jan 2000", "01/01/2000", "2015/10/10"))
[1] "2000-01-01" "2000-01-01" "2015-10...
Displaying the build date
...s well and good except it means nothing to most of the users, who want to know if they have the latest build - they tend to refer to it as "last Thursday's" rather than build 1.0.8.4321.
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Can dplyr package be used for conditional mutating?
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dplyr now has a function case_when that offers a vectorised if. The syntax is a little strange compared to mosaic:::derivedFactor as you cannot access variables in the standard dplyr way, and need to declare the mode of NA, but it ...
Constructor overload in TypeScript
...parameters that may not have all properties of the object defined. You can now safely write any of these:
const box1 = new Box();
const box2 = new Box({});
const box3 = new Box({x:0});
const box4 = new Box({x:0, height:10});
const box5 = new Box({x:0, y:87,width:4,height:0});
// Correctly reports...
Why is it string.join(list) instead of list.join(string)?
...ace UCS2/4. To calculate total buffer length of UTF-8 strings it needs to know character coding rule.
At that time, Python had already decided on a common sequence interface rule where a user could create a sequence-like (iterable) class. But Python didn't support extending built-in types until 2.2....
Rails: Open link in new tab (with 'link_to')
...is one needs to add on the 'rel' attribute to the code.
rel: 'noopener'
Now the link_to should be:
<%= link_to image_tag("facebook.png", class: :facebook_icon, alt: "Facebook"), "http://www.facebook.com/mypage", target: :_blank, rel: 'noopener %>
rubocop docs
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Collapse sequences of white space into a single character and trim string
...h, but I challenge your definition of "easy". Sincerely, former Python guy now in ObjC-land ;-)
– JK Laiho
May 31 '12 at 9:17
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Django dynamic model fields
....create(value='unkown')
ynu = EnumGroup.objects.create(name='Yes / No / Unknown')
ynu.enums.add(self.yes)
ynu.enums.add(self.no)
ynu.enums.add(self.unkown)
Attribute.objects.create(name='fever', datatype=Attribute.TYPE_ENUM,\
enum_group=ynu)
# When you regist...
append to url and refresh page
...aram=42';
We don't have to alter the entire url, just the query string, known as the search attribute of location.
When you are assigning a value to the search attribute, the question mark is automatically inserted by the browser and the page is reloaded.
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Why doesn't django's model.save() call full_clean()?
I'm just curious if anyone knows if there's good reason why django's orm doesn't call 'full_clean' on a model unless it is being saved as part of a model form.
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