logic error or problem with if stmt ?

[npd_ddit]

main()
{
float a=0.7;
if(a<0.7) cout<<"true" ;else cout<<"false";
}
problem---> it prints true .....
when 0.7 is replaced everywhere with 0.8 it displays false
again with 0.9 , it displays true..
typically only for 0.7 and 0.9 it gives different answer ,then the conventional logical answer..why so??

[mrinal.s2008]

change your if condition as below

if(a < 0.7f)

I do not remember the exact reason for the behavior in your code, it has got something to do with how floats are treated by the hardware.
Someone please elaborate.

[Agni]

This thread here talks about float comparisons. There's a good link available in the thread about the same.

Thread1

[npd_ddit]

thank you mrinal..
i think it is because the default datatype is double ..hence to do a proper comparison of float values,we have to specify it .
thanks.

change your if condition as below

if(a < 0.7f)

I do not remember the exact reason for the behavior in your code, it has got something to do with how floats are treated by the hardware.
Someone please elaborate.