problem to find the index in 999×6 double

Hi, D = 999×6 double, I tried to use the function find to locate 0.5 values index in first two columns separately(x=999×1 double and y=999×1 double) but after several methods of trying I got same answers that are 1×0 empty double row vector and 0×1 empty double column vector. Please guide me to find the decimals 0.5001 values in the long vector. Thank you

Best regards, Venkat

[Stephen23]

Use a tolerance and do not test for equivalence:

https://www.mathworks.com/matlabcentral/answers/57444-faq-why-is-0-3-0-2-0-1-not-equal-to-zero

https://www.mathworks.com/matlabcentral/answers/69-why-does-1-2-3-1-3-not-equal-zero

and a thousand other times this topic comes up.

Answer 1

[KSSV]

You define a small tolerance value and find the difference less then this tolerance. This is the way to find flottant points.

tol=10^-6;
idx=find(abs(col-0.5001)<=tol);

[Venkat Ta]

Super its works thanks.

[Valerii Abramenko]

Nice promt! Thank you