Questions tagged [sub-array]

A sub-array is a subset of an array.

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In Swift, Array [String] slicing return type doesn't seem to be [String]

I'm slicing an array of strings and setting that to a [String] variable, but the type checker is complaining. Is it a possible compiler bug? var tags = ["this", "is", "cool"] tags[1..<3] var someTags: [String] = tags[1..<3]
Liron Shapira
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How to get a subArray from Swift 2.0

I keep trying to search for the proper way to get a sub array in Swift but I am missing something here. This code doesn't work because rowArray.append(row) throws an error that states. Cannot convert value of type 'ArraySlice' to specified…
Skyler Lauren
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How to use MPI_Type_create_subarray?

It is clear that its arguments are: int MPI_Type_create_subarray( int ndims, int array_of_sizes[], int array_of_subsizes[], int array_of_starts[], int order, MPI_Datatype oldtype, MPI_Datatype *newtype ); However, I cannot understand…
Pippo
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How to properly return part of ArrayList in Java?

I have a class SomeClass with a static member myMap enter code herethat has the form HasmMap> which gets de-serialized from a file. I have a method public ArrayList getList(final String key, final int…
I Z
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Group row data by one column value and populate a subarray in each group with the other column value

I want to group the data in an array with associative rows. Group should be determined by the type value and all label_id values within each group should be formed into a subarray. Sample input: $array = [ ['type' => 'AAA', 'label_id' =>…
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Julia: does an Array contain a specific sub-array

In julia we can check if an array contains a value, like so: > 6 in [4,6,5] true However this returns false, when attempting to check for a sub-array in a specific order: > [4,6] in [4,6,5] false What is the correct syntax to verify if a specific…
Nicky Feller
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R array manipulation

In python lists can be sliced like this x[4:-1] to get from the fourth to the last element. In R something similar can be accomplished for vectors with x[4:length(x)] and for multidimensional arrays with something like x[,,,,4:dim(x)[5],,,]. Is…
momeara
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Maximizing a particular sum over all possible subarrays

Consider an array like this one below: {1, 5, 3, 5, 4, 1} When we choose a subarray, we reduce it to the lowest number in the subarray. For example, the subarray {5, 3, 5} becomes {3, 3, 3}. Now, the sum of the subarray is defined as the sum of…
AvinashK
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Filter a 2D numpy array

I want to have a sub array (between min and max) of a numpy 2D ndarray xy_dat = get_xydata() x_displayed = xy_dat[((xy_dat > min) & (xy_dat < max))] min and max are float in order to be compare with the first value of the array…
reynum
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Two dimensional arrays and pointers

I have the following code snippet: char board[3][3] = { {'1','2','3'}, {'4','5','6'}, {'7','8','9'} }; printf("address of board : %p\n", &board); printf("address of…
intex0075
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Subarray from NSMutableArray

I have a NSMutableArray with many objects. Can i extract a subarray from index range 'i' to 'j' directly? Yeah i know i can do a loop and use objectAtIndex:x and extract each object to a new. I need to call a method which input is an array and want…
Jorge Vega Sánchez
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Numpy unique 2D sub-array

I have 3D numpy array and I want only unique 2D-sub-arrays. Input: [[[ 1 2] [ 3 4]] [[ 5 6] [ 7 8]] [[ 9 10] [11 12]] [[ 5 6] [ 7 8]]] Output: [[[ 1 2] [ 3 4]] [[ 5 6] [ 7 8]] [[ 9 10] [11 12]]] I tried convert…
Petr
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How to extract all possible matching arrays of objects from one array of objects?

I have an array of objects, e.g. var arr = [ {"a": "x"}, {"b": "0"}, {"c": "k"}, {"a": "nm"}, {"b": "765"}, {"ab": "i"}, {"bc": "x"}, {"ab": "4"}, {"abc": "L"} ]; Let's say I am only interested in objects whose…
lyrically wicked
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Find the first occurrence/starting index of the sub-array in C#

Given two arrays as parameters (x and y) and find the starting index where the first occurrence of y in x. I am wondering what the simplest or the fastest implementation would be. Example: when x = {1,2,4,2,3,4,5,6} y = {2,3} result …
Jeff
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Taking views of views allocate in Julia

I noticed that taking views of non-"fast linear indexed" subarray allocates, while this is possible on classical vectors. Any idea, how to make this allocation free? Here is an illustration of the behavior: function temp!(lin::Vector{Int},…
Tanj
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