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How to count TRUE values in a logical vector
...) is more self explaining. Though, I think with a simple task like this it does not really make a difference...
If it is a large vector, you probably should go with the fastest solution, which is sum(z). length(z[z==TRUE]) is about 10x slower and table(z)[TRUE] is about 200x slower than sum(z).
Su...
How does one reorder columns in a data frame?
...2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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Delete all Duplicate Rows except for One in MySQL? [duplicate]
...Editor warning: This solution is computationally inefficient and may bring down your connection for a large table.
NB - You need to do this first on a test copy of your table!
When I did it, I found that unless I also included AND n1.id <> n2.id, it deleted every row in the table.
If you ...
What is the difference between __init__ and __call__?
...is used to initialise newly created object, and receives arguments used to do that:
class Foo:
def __init__(self, a, b, c):
# ...
x = Foo(1, 2, 3) # __init__
The second implements function call operator.
class Foo:
def __call__(self, a, b, c):
# ...
x = Foo()
x(1, 2, 3) # ...
Is there a way to get colored text in Github Flavored Markdown? [duplicate]
I need to document a library on github that output colored text in the terminal.
5 Answers
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Simple way to copy or clone a DataRow?
...nal Row are then free to change but we still have another saved copy which doesn't change. Is this the correct way to do it?
...
Prevent dialog dismissal on screen rotation in Android
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It says that onAttach is deprecated now. What should be done instead?
– farahm
Sep 20 '16 at 7:44
3
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How to increase heap size of an android application?
...rbread and above.
The only way to have as large a limit as possible is to do memory intensive tasks via the NDK, as the NDK does not impose memory limits like the SDK.
Alternatively, you could only load the part of the model that is currently in view, and load the rest as you need it, while removi...
Does this app use the Advertising Identifier (IDFA)? - AdMob 6.8.0
...g me if this app users IDFA. I'm using the latest Admob SDK or 6.8.0 and I don't know if it uses IDFA or not, and if it does which check boxes should I hit X.X
...
Ruby : How to write a gem? [closed]
...re any good tutorials, screencasts, etc., which helped you learning how to do it ?
3 Answers
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