Find function can not find vector element index

I am trying a find an specific value from an array like below. But even if the value 67.2 is there the command window shows error.

>>range=1:0.1:100;
>>find(range==67.2)
1×0 empty double row vector

I have also tried many other work arounds but it seems to there is some inherent problem. Or there might not be. I am using MATLAB Online 2020a version.

Thanks in advance.

Answer 1

[Geoff Hayes]

You can't use the equality operator == with doubles. See Floating-Point Numbers for details. Instead you need to use a tolerance check when comparing. So something like

find(abs(range - 67.2) < 0.00001)

In the above, we look at the absolute difference between the elements of the range array and 67.2. If that difference is less than some tolerance, then we consider the two numbers to be "close enough" to each other.

[Md. Mahfuz Talukdar]

Thanks a lot. It works perfectly.