Hi, I assume the coefficients have been entered using with MATLAB code like this
coef = [0.05 0.15]
Since MATLAB defaults to double, these coefficients will be the most accurate representation of 0.05 and 0.15 that a double can hold. To see how close, you could do
mat2str(coef,18)
ans =
'[0.0500000000000000028 0.149999999999999994]'
If you've constructed your model to use coef with single precision run-time parameters, then the original doubles will need to be quantized to singles. Under the hood, the Simulink model is doing the equivalent of
runTimeCoef = single(coef)
To see what this produces, you could do
mat2str(runTimeCoef,18)
ans =
'[0.0500000007450580597 0.150000005960464478]'
As you can see, the before and after values are difference.
'[0.0500000000000000028 0.149999999999999994]'
'[0.0500000007450580597 0.150000005960464478]'
Hence, the warning about precision loss.
One way to avoid this is to pre-quantized the coefficients before supplying them to Simulink
coef = single([0.05 0.15])
The parameter value used by the Simulink model will still be identical
'[0.0500000007450580597 0.150000005960464478]'
but the warning would go away.
As of R2016b, you can also suppress individual warnings after you've reviewed them and determined the warning to be benign.
