ne,~=

Create two vectors containing both real and imaginary numbers, then compare the vectors for inequality.

A = [1+i 3 2 4+i]; B = [1 3+i 2 4+i]; A ~= B

ans =1x4 logical array1 1 0 0

Thenefunction tests both real and imaginary parts for inequality, and returns logical1(true) where one or both parts are not equal.

创建一个特征向量。

M ='magenta';

Test for the presence of a specific character using~=.

M ~='q'

ans =1x7 logical array1 1 1 1 1 1 1

The value of logical1(true) indicates the absence of the character'n'. The character is not present in the vector.

Create a categorical array with two values:'heads'and'tails'.

A = categorical({'heads''heads''tails';'tails''heads''tails'})

A =2x3 categoricalheads heads tails tails heads tails

Find all values not in the'heads'category.

A ~='heads'

ans =2x3 logical array0 0 1 1 0 1

A value of logical1(true) indicates a value not in the category. SinceAonly has two categories,A ~= 'heads'returns the same answer asA == 'tails'.

Compare the rows ofAfor inequality.

A(1,:) ~= A(2,:)

ans =1x3 logical array1 0 0

A value of logical1(true) indicates where the rows have unequal category values.

Many numbers expressed in decimal text cannot be represented exactly as binary floating numbers. This leads to small differences in results that the~=operator reflects.

Perform a few subtraction operations on numbers expressed in decimal and store the result inC.

C = 0.5-0.4-0.1

C = -2.7756e-17

With exact decimal arithmetic,Cshould be equal toexactly0. Its small value is due to the nature of binary floating-point arithmetic.

CompareCto0for inequality.

C ~= 0

ans =logical1

Compare floating-point numbers using a tolerance,tol, instead of using~=.

tol = eps(0.5); abs(C-0) > tol

ans =logical0

The two numbers,Cand0, are closer to one another than two consecutive floating-point numbers near0.5. In many situations,Cmay act like0.

Compare the elements of twodatetimearrays for inequality.

Create twodatetimearrays in different time zones.

t1 = [2014,04,14,9,0,0;2014,04,14,10,0,0]; A = datetime(t1,'TimeZone','America/Los_Angeles'); A.Format ='d-MMM-y HH:mm:ss Z'

A =2x1 datetime14-Apr-2014 09:00:00 -0700 14-Apr-2014 10:00:00 -0700

t2 = [2014,04,14,12,0,0;2014,04,14,12,30,0]; B = datetime(t2,'TimeZone','America/New_York'); B.Format ='d-MMM-y HH:mm:ss Z'

B =2x1 datetime14-Apr-2014 12:00:00 -0400 14-Apr-2014 12:30:00 -0400

Check where elements inAandBare not equal.

A~=B

ans =2x1 logical array0 1

Since R2023a

Create two tables and compare them. The row names (if present in both) and variable names must be the same, but do not need to be in the same orders. Rows and variables of the output are in the same orders as the first input.

A = table([1;2],[3;4],VariableNames=["V1","V2"],RowNames=["R1","R2"])

A=2×2 tableV1 V2 __ __ R1 1 3 R2 2 4

B = table([4;2],[3;1],VariableNames=["V2","V1"],RowNames=["R2","R1"])

B=2×2 tableV2 V1 __ __ R2 4 3 R1 2 1

A ~= B

ans=2×2 tableV1 V2 _____ _____ R1 false true R2 true false