创建一个3 x-3矩阵，然后测试每列的所有非零元素。

A = [0 0 3;0 0 3;0 0 3]

A =3×30 0 3 0 0 3 0 0 3

b =所有（a）

b =1x3逻辑数组0 0 1

创建一个小数值和测试的向量，哪些值小于0.5。

a = [0.53 0.67 0.01 0.38 0.07 0.42 0.69];b =（a <0.5）

b =1x7 logical array0 0 1 1 1 1 0

这output is a vector of logical values. The全部function reduces such a vector of logical values to a single condition. In this case,B =全部（a <0.5）产生逻辑0。

This makes全部特别有用if语句。

如果全部（a <0.5）

%do something

else

％做其他事情

end

这code is executed depending on a single condition, rather than a vector of possibly conflicting conditions.

Create a 3-by-7-by-5 multidimensional array and test to see if all of its elements are less than 3.

a = rand（3,7,5） * 5;b = all（a（:) <3）

b =logical0

您还可以测试大于零的元素的数组。

b =全部(A(:) > 0)

b =logical1

这syntax一个（：）turns the elements ofAinto a single column vector, so you can use this type of statement on an array of any size.

Create a 3-by-3 matrix.

A = [0 0 3;0 0 3;0 0 3]

A =3×30 0 3 0 0 3 0 0 3

Test the rows ofA对于所有非零元素，通过指定dim = 2。

B =全部（A，2）

b =3x1 logical array0 0 0

Create a 3-D array and determine if all elements in each page of data (rows and columns) are zero.

A(:,:,1) = [2 1; 3 5]; A(:,:,2) = [0 0; 0 0]; A(:,:,3) = [-2 9; 4 1]; B = all(A,[1 2])

b =1x1x3逻辑数组B(:,:,1) = 1 B(:,:,2) = 0 B(:,:,3) = 1