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How to return the last value of a vector in R - 2 programming examples - length function vs. tail function - Access bottom element of array.

Java answers related to “storing last element of string in java” ... get last index of array java · find last element in array in java · how to get last ...

Position returns a list of positions in a form suitable for use in Extract, ReplacePart, and MapAt. The form is different from the one used in Part. Position looks only for matches to values in Association objects that appear in expr. It returns any part specifications within Association objects in the form Key [ k].

But when I have a matrix mat ,why I cannot do this with same method? mat = Partition[Range[12], ...

There is: negative indices: lst[-2].

Last[expr] gives the last element in expr. Last[expr, def] gives the last element if there are any elements, or def otherwise.

Nov 18, 2017 · I have a little problem with getting element from nested list. I have list like this: list{{4, 1}, {3, 2}, {3, 3}, {4, 4}} I want to get single number from this list, e.g. 4. How can I get it? I've tried something like. list[[1]] and other things. I've tried many times and failed. Would be great if anyone could show me this. Thanks!

Get Elements of Lists. Lists are very important structures in the Wolfram Language. Lists allow you to treat any kind of collection of objects as a single entity. Sometimes you need to pick out or extract individual elements or groups of elements from …

26.12.2016 · Mathematica Stack Exchange is a question and answer site for users of Wolfram Mathematica. It only takes a minute to sign up. Sign up to join this community. Anybody can ask a question ... So I can do this to get the first and last element: a[[{1, -1}]] (* {1, 5} *)

S[-1] selects the last element, S[-2] the second last, and so on. ... To extract the contents of a list or set L as a sequence, use the op(L) function or ...

... the last element in expr. Last[expr, def] gives the last element if there are any elements, or def otherwise. ... Extract the last element of a list:.

List Manipulation. Lists are central constructs in the Wolfram Language, used to represent collections, arrays, sets, and sequences of all kinds. Lists can have any structure and size and can routinely involve even millions of elements. Well over a thousand built-in functions throughout the Wolfram Language operate directly on lists, making ...

Get Elements of Lists. Lists are very important structures in the Wolfram Language. Lists allow you to treat any kind of collection of objects as a single entity. Sometimes you need to pick out or extract individual elements or groups of elements from a list. Set up a list of the first 10 squares (stored as v ):

Dec 27, 2016 · It is a elemental question maybe,but I am confusing still.If I have a 1-dimension list list. a = Range[5] (* {1, 2, 3, 4, 5} *) So I can do this to get the first and last element: a[[{1, -1}]] (* {1, 5} *) But when I have a matrix mat,why I cannot do this with same method? mat = Partition[Range[12], 4]; mat[[{{1, 1}, {-1, -1}}]]

17.04.2010 · You can use end notation to indicate the last element. data(2:end) returns a vector containing elements in the vector data from element 2 to the last element. Or if data is a character array, it returns the second character all the way to the last character. And data(end) returns the last element.. This can be done with matrices too, i.e. data(2:end,5:end).

Drop[list, n] gives list with its first n elements dropped. Drop[list, -n] gives list with its last n elements dropped. Drop[list, {n}] gives list with its n\[Null]^th element dropped. Drop[list, {m, n}] gives list with elements m through n dropped. Drop[list, {m, n, s}] gives list with elements m through n in steps of s dropped. Drop[list, seq1, seq2, ...] gives a nested list in which ...

Work with Nested Lists. Nested lists are lists within a list; they are the principal structure for data in the Wolfram Language and allow for high-dimension arrays and ragged datasets as well as common uses such as matrices. Create a list of lists to work with: Copy to clipboard. Matrices in the Wolfram Language are represented as nested lists.

Elements of Lists. The Wolfram Language provides a carefully chosen set of functions for accessing elements of lists using either indices or positions, or using patterns or criteria for their values. list [ [...]] ( Part) — parts of lists, resettable with =.

Last[expr] gives the last element in expr. Last[expr, def] gives the last element if there are any elements, or def otherwise.

05.04.2017 · Every time you change the length of a list in Mathematica you cause a reallocation of the list, which takes O(n) rather than O(1) time. Though no "DeleteFrom" function exists, if it did it would be no faster than a = Delete[a, x].. If you can create in advance a list of all the elements you wish to delete and delete them all at once you will get much better performance.

An iterator doesn't necessarily have a last element. Consider the following: [code]def it(): i = 0 while True: yield i i += 1 # ints = it() [/code]ints is ...

Lists are central constructs in the Wolfram Language, used to represent collections, arrays, sets, and sequences of all kinds. Lists can have any structure and size and can routinely involve even millions of elements. Well over a thousand built-in functions throughout the Wolfram Language operate directly on lists, making lists a powerful vehicle for interoperability.

29.10.2013 · The task I have is pretty simple but I can not solve it in mathematica. Given a list. myList = {1, 3, 4} I would like to get the position of entries smaller than a number - say 2 in the example above. Attempts such as . Position[myList, #[[1]] < 2 &] Position[myList, # < 2 &] which would be similar to the function SELECT don't work.

Work with Nested Lists. Nested lists are lists within a list; they are the principal structure for data in the Wolfram Language and allow for high-dimension arrays and ragged datasets as well as common uses such as matrices. Create a list of lists to work with: Copy to clipboard. Matrices in the Wolfram Language are represented as nested lists.

а 1.3 Getting pieces of lists. First[list] the first element in list. Last[list] the last element. Part[list, n] or list[[n]] the nth element.