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How to count TRUE values in a logical vector
...le(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing returns values)
So I think the safest is to use na.rm = TRUE:
sum(z, na.rm = TRUE) # best way to count TRUE values
(which gives 1). I think that table solution is less efficient (look at the code o...
Using @include vs @extend in Sass?
...background-color: $main-color
border: 1px solid black
border-radius: 0.2em
&:hover, &:active
background-color: $active-color
a
+button
button
+button(pink, red)
Results in:
a {
background-color: lightgrey;
border: 1px solid black;
border-radius: 0.2em;
}
a:hover, a...
Is it a bad practice to use negative margins in Android?
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In 2010, @RomainGuy (core Android engineer) stated that negative margins had unspecified behavior.
In 2011, @RomainGuy stated that you can use negative margins on LinearLayout and RelativeLayout.
In 2016, @RomainGuy stated tha...
Programmatically access currency exchange rates [closed]
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Seer
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answered Oct 8 '08 at 10:23
GregGreg
286k...
Capturing multiple line output into a Bash variable
...d in the variable — newlines, tabs, multiple blanks and all — whereas (2) the unquoted version (echo $RESULT) replaces each sequence of one or more blanks, tabs and newlines with a single space. Thus (1) preserves the shape of the input variable, whereas (2) creates a potentially very long singl...
Copy folder recursively, excluding some folders
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Use rsync:
rsync -av --exclude='path1/to/exclude' --exclude='path2/to/exclude' source destination
Note that using source and source/ are different. A trailing slash means to copy the contents of the folder source into destination. Without the trailing slash, it means copy the folder so...
how to remove only one style property with jquery
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2 Answers
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Best way to reverse a string
I've just had to write a string reverse function in C# 2.0 (i.e. LINQ not available) and came up with this:
48 Answers
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Eclipse: Referencing log4j.dtd in log4j.xml
...native:
<!DOCTYPE log4j:configuration PUBLIC
"-//APACHE//DTD LOG4J 1.2//EN" "http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/xml/doc-files/log4j.dtd">
It is similar to @FrVaBe's response, but on the plus side, does not require any further Eclipse configuration (i.e., if you'r...
Trying to git pull with error: cannot open .git/FETCH_HEAD: Permission denied
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29 Answers
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