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Extracting specific columns in numpy array
This is an easy question but say I have an MxN matrix. All I want to do is extract specific columns and store them in another numpy array but I get invalid syntax errors.
Here is the code:
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Subset of rows containing NA (missing) values in a chosen column of a data frame
...er use =='NA' to test for missing values. Use is.na() instead. This should do it:
new_DF <- DF[rowSums(is.na(DF)) > 0,]
or in case you want to check a particular column, you can also use
new_DF <- DF[is.na(DF$Var),]
In case you have NA character values, first run
Df[Df=='NA'] <- N...
What happens if I define a 0-size array in C/C++?
...ually happens if I define a zero-length array int array[0]; in code? GCC doesn't complain at all.
7 Answers
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Angular ng-repeat Error “Duplicates in a repeater are not allowed.”
...13/06/15/duplicates-in-a-repeater-are-not-allowed-in-angularjs/
AngularJS does not allow duplicates in a ng-repeat directive. This means if you are trying to do the following, you will get an error.
// This code throws the error "Duplicates in a repeater are not allowed.
// Repeater: row in [1,1,1...
Intent - if activity is running, bring it to front, else start a new one (from notification)
...is site: Make sure to get rid of other changes you tried and make sure you do this change to the correct activity. Took me far too long to find out that this solution would've worked if I hadn't tried other solutions as well (e.g. overriding onNewIntent and setting flags)
– lu...
check if a std::vector contains a certain object? [duplicate]
...egin(), v.end(), x) != v.end()) {
/* v contains x */
} else {
/* v does not contain x */
}
Checking if v contains elements (is non-empty):
if(!v.empty()){
/* v is non-empty */
} else {
/* v is empty */
}
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In Python, when to use a Dictionary, List or Set?
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A list keeps order, dict and set don't: when you care about order, therefore, you must use list (if your choice of containers is limited to these three, of course;-).
dict associates with each key a value, while list and set just contain values: very differ...
How to “add existing frameworks” in Xcode 4?
I can't find the good old "Add existing frameworks" option. How do I do this?
10 Answers
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How to reverse a 'rails generate'
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Btw, how do I use this command to delete a scaffold? The model and controller work fine...but how do I completely reverse a scaffold?
– marcamillion
Nov 12 '10 at 6:08
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Visual Studio: How to show Overloads in IntelliSense?
... In vscode this works too and you can use Alt + Up or Alt + Down to navigate between them.
– Juan De la Cruz
May 12 at 21:31
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