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Remove duplicated rows using dplyr
...mple(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data frame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need...
What is the difference between Modal and Push segue in Storyboards?
Can someone explain to me what is the exact difference between modal and push segue?
4 Answers
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What is the Scala identifier “implicitly”?
...ave seen a function named implicitly used in Scala examples. What is it, and how is it used?
3 Answers
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Android: Generate random color on click?
I have an ImageView , in which I am programmaticly creating drawables and presenting them to the user. My goal is to click on said ImageView and change the drawable's color.
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Difference between validate(), revalidate() and invalidate() in Swing GUI
...idate() marks the container as invalid. Means the content is somehow wrong and must be re-laid out. But it's just a kind of mark/flag. It's possible that multiple invalid containers must be refreshed later.
validate() performs relayout. It means invalid content is asked for all the sizes and all th...
Python hashable dicts
As an exercise, and mostly for my own amusement, I'm implementing a backtracking packrat parser. The inspiration for this is i'd like to have a better idea about how hygenic macros would work in an algol-like language (as apposed to the syntax free lisp dialects you normally find them in). Because...
Decimal precision and scale in EF Code First
... changes, from EF 4.1 onwards the ModelBuilder class is now DbModelBuilder and there is now a DecimalPropertyConfiguration.HasPrecision Method which has a signature of:
public DecimalPropertyConfiguration HasPrecision(
byte precision,
byte scale )
where precision is the total number of digits the...
unable to copy/paste in mingw shell
I just installed MinGW on Windows and I'm unable to copy/paste as I am used to on Linux or even PuTTY. What is the trick for copying and pasting text (e.g. from chrome) into MinGW shell?
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How do I do a case-insensitive string comparison?
...hos”) has all three: uppercase at the front, lowercase final at the end, and lowercase nonfinal at the third position. If your two strings are Σίσυφος and ΣΊΣΥΦΟΣ, then your approach fails, because those are supposed to be the same case insensitively.
– tchrist...
How to jump back to NERDTree from file in tab?
...ws (so you could hop between the NERDTree window, the file you are editing and the help window, for example... just hold down Ctrl and press w twice).
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