if else loop

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I have a variable "v" in my code which after calculation gets value either 1 or 1.0000 And 1 is not equal to 1.0000 here. I want to apply a if else if loop as follows : if v==1 statements elseif v==1.0000 statements else statements end

But this is not working. Please tell me the correct way to do it. Matlab isn't executing "v==1.0000". Why??

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Walter Roberson 2012-4-9

There is no such thing as an "if loop". "if" does not loop: it executes once. "if" might be coded within a loop, but it is not a loop.

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Answer 1

Daniel Shub 2012-4-9

在 MATLAB Online 中打开

0 个投票

Try

format long

and then look at your v. You can also look at

v-1

What you will see is that when MATLAB says v is equal to 1.0000, what MATLAB is telling you is that v is not equal to 1, but rather something slight more than 1.

There is a huge discussion here (and else where) on floating point comparisons.