This question already has answers here:
How do I pick randomly from an array?
(7 answers)
Closed 7 years ago.
Select a element in the array randomly WITHOUT using the Random class.
id={1,2,3,4,5}
Is there any method which belongs to the Array class that is used to randomly select an element?
You can use the sample method
[:foo, :bar].sample # => :foo, or :bar :-)
Credit this SO question/answer
Related
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What does `:_*` (colon underscore star) do in Scala?
(4 answers)
Closed 3 years ago.
I'm wondering if it's possible to convert an array of elements to the elements themselves. For my example, I'm trying to pass individual strings into a function whose arguments are a variable number of strings. I currently have an array of strings and am trying to pass them into .toDF (which takes a variable number of strings). This is what I have:
.toDF((df.columns)
How can I convert this array into the individual elements?
You can do this with scala's splat operator (more information here):
.toDF(df.columns: _*)
This question already has answers here:
Find number deleted from array
(2 answers)
Closed 5 years ago.
I have two arrays a and b. a always has one element more than b, and the arrays are mixed.
a = [1,5,7,2,4]
b = [2,4,7,1]
I want to find the extra element in a. The output should be 5.
What is the best approach in ruby? Is it good idea to use loop?
I think this is the best built-in function to get what you expect
(a - b).pop
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Check if elements in two arrays are same irrespective of index
(2 answers)
How do I check in Swift if two arrays contain the same elements regardless of the order in which those elements appear in?
(10 answers)
Closed 5 years ago.
I tried using sets but obviously that doesn't work. I need a function to be able to work like this:
let Array1 = [2,2,1,1]
let Array2 = [2,1,2,1]
let Array3 = [2,2,2,1]
I need my function to be able to recognize that Array1 and Array2 are equal without thinking that Array3 is the same. Any thoughts?
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Combine two Arrays into Hash
(8 answers)
Closed 6 years ago.
If i have two arrays containing about 20 separate values is it possible to combine the two into a hash? With the contents of one array acting as the keys and the other as the values?
Sure, very simple
Hash[[1,2,3,4].zip([5,6,7,8])]
=> {1=>5, 2=>6, 3=>7, 4=>8}
But it might be a problem if the arrays have not the same size.
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How to check for Is Not Null in VBA?
(2 answers)
Closed 7 years ago.
While retrieving data from a database into an array one of my array elements is (or appears to be) 'Null', as the watch window shows.
However, pCurveDefinitions(2,0)=Null return FALSE.
How can I make the check in such a way it returns TRUE?
This is just a different test, like IsError, you should use IsNull(pCurveDefinitions(2,0))!