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Re: finding index of any element in a matrix
Posted:
Jun 24, 2013 2:07 PM


On Monday, June 24, 2013 4:03:41 PM UTC+5:30, Nasser M. Abbasi wrote: > On 6/24/2013 5:13 AM, asif khan wrote: > > > > > > > > eg,R = rand(3,3) > > > > > > R = > > > > > > 0.4820 0.2262 0.2518 > > > 0.1206 0.3846 0.2904 > > > 0.5895 0.5830 0.6171 > > > > > > I = find(R==0.6171) > > > > > > I = > > > > > > Empty matrix: 0by1 > > > that is the problem... is there any precision problem??? > > > > > > > Yes. You should never really use .EQ. with floating points. > > > > In addition, what you see on the screen is not the full number > > any way. > > > > EDU>> format short > > EDU>> R=rand(2) > > 0.8491 0.6787 > > 0.9340 0.7577 > > > > EDU>> find(R==0.7577) > > Empty matrix: 0by1 > > > > Error using format > > EDU>> R > > 0.849129305868777 0.678735154857773 > > 0.933993247757551 0.757740130578333 > > > > To do an .EQ. on floating point (or any comparison, < or > etc..) > > you should use the abs/epsilon method. This is discussed in > > many places. > > > > Nasser
Thank you very much for your reply...
i got the idea..



