Matrix manipulation by function

2017 4 6
2 个回答
回答已采纳
更新时间：2017 4 7
3 次查看（30 天）

0 个投票

Dear all, For a given matrix (square) i need to eliminate some elements (some rows and columns)
A =
35 6 19
3 7 23
31 2 27
I need only the second (not the first and the third) row and column : the eliminated are stocked in a vector
B = (1 3)
So : some function (A, B) :::> the result C = 7
function (A, B) = C

2 个评论
显示 无 隐藏 无

KSSV
KSSV 2017-4-6
iwant = A(2,2)
wont it solve the purpose?
Lila wagou
Lila wagou 2017-4-6
Dear KSSV, i need a function for lot of use
A1 =
35 6 19
3 7 23
31 2 27
and
B1 = (1 3)
C1 = 7
or
A2 =
35 6 19 11
3 7 23 44
31 2 27 55
31 2 27 55
and
B2 = (2 3)
C2 =
35 11
31 55

请先登录，再进行评论。

请先登录，再回答此问题。

 采纳的回答

Andrei Bobrov
Andrei Bobrov 2017-4-6

0 个投票

ii = num2cell([1;1]*setdiff(1:length(A),B(:)'),2);
out = A(ii{:});

8 个评论
显示 6更早的评论 隐藏 6更早的评论

Lila wagou
Lila wagou 2017-4-6
Dear Andrei; please why 2 in ,B(:)'),2); thanks
Andrei Bobrov
Andrei Bobrov 2017-4-6
编辑：Andrei Bobrov 2017-4-6
Please read about num2cell, it's 'dim'.
Lila wagou
Lila wagou 2017-4-6
Dear Andrei; thanks the explication, is it possible to get only the the first and the third (not the second) rows and columns : the wanted are stocked in a B vector
A =
35 6 19
3 7 23
31 2 27
B = (1 3)
C = function (A, B)
C =
35 19
31 27
Lila wagou
Lila wagou 2017-4-7
Dear Andrei; Thank you a lot for your valued assistance.
judy abbott
judy abbott 2017-4-7
Hy Lila, Hy Andrei Bobrov, i have a same need but for a vector, for a V_old vector i want to insert the V_ins vector in the order of V_ord vector (the value of 10 replace the 1 element of V_old, the value of 20 replace the 3 element of V_old):
V_old = zeros(1,3);
V_ins = [10 20];
V_ord = [1 3];
I want to write a function
V_new = MyFunction(V_old, V_ins, V_ord)
to get V_new = 10 0 20
Thank
Andrei Bobrov
Andrei Bobrov 2017-4-7
V_new = V_old;
V_new(V_ord) = V_ins;
Lila wagou
Lila wagou 2017-4-7
Dear Andrei; please how to trait a vector (eliminate the elements stocked in a vector by order)
A = [10 52 33]
B = [3]
ii = num2cell([1]*setdiff(1:length(A),B(:)'),1);
out = A(ii{:});
i get out = 52 so i must get out = 10 52

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Operators and Elementary Operations 的更多信息

产品

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by