How can I count how many numbers are different from '-1'?

2 次查看（过去 30 天）
Davide Conti
Davide Conti 2019-11-1
评论： Walter Roberson 2019-11-5
Hi,
Example: Suppose we a have a matrix A
A= [1 -1 0 -1 0 0 -1 0 -1 -1 -1 -1 -1 -1 -1]
How can I count how many numbers are different from '-1'?
  2 个评论
Shubhashree Bal
Shubhashree Bal 2019-11-1
Search for how many negative number exists in A. than subtract that from length of array. Or Write a loop for how many positive number exists in array.
Code attached below:
Close all;
clear all;
A= [1 -1 0 -1 0 0 -1 0 -1 -1 -1 -1 -1 -1 -1];
count = 0;
for i = 1: length(A)
if(A(i)>=0)
count = count +1;
end
end
Davide Conti
Davide Conti 2019-11-5
Ok thanks, but if i wanted to do it for every line of my matrix?
For examples:
1 -1 0 -1 0 0 -1 0 -1
4 2 3 -1 0 3 1 2 -1
in this case for the first row the numbers different form '-1' are 5, in the second row they are 7.
With your loop it comes out that in the second row they are 12, because it considers the first row.

请先登录，再进行评论。

请先登录，再回答此问题。

回答（2 个）

Fangjun Jiang
Fangjun Jiang 2019-11-1
start with B=A~=-1
Pedro Martinez
Pedro Martinez 2019-11-1
Total = sum (A==-1);

类别

在 Help Center 和 File Exchange 中查找有关 Operators and Elementary Operations 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by