大约有 45,000 项符合查询结果(耗时:0.0565秒) [XML]

https://stackoverflow.com/ques... 

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...
https://stackoverflow.com/ques... 

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. ...
https://stackoverflow.com/ques... 

Can dplyr package be used for conditional mutating?

... 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 ...
https://stackoverflow.com/ques... 

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...
https://stackoverflow.com/ques... 

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....
https://stackoverflow.com/ques... 

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 ...
https://stackoverflow.com/ques... 

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 ...
https://stackoverflow.com/ques... 

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...
https://stackoverflow.com/ques... 

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. ...
https://stackoverflow.com/ques... 

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. ...