Matlab coder error : This expression has size [:? x 1] ?

Hi While using matlab coder codegen. I am getting following error.

Why output of find command is uncertain?

[dpb]

Because zoomMax could be empty if all(zoom~=6)==True

I don't have codegen so I don't know if it is smart enough to read the second optional argument or not but even if it is, that isn't enough to guarantee the length of the return is one and only one element.

Answer 1

[Walter Roberson]

dpb is correct that zoomMax could be empty.

Even if it is not empty, J(1:zoomMax) would be variable length, leading positionX to be variable length, along with a number of other expressions on the following lines, right through to halfpx being variable length.

All of those variables need to be either noted with coder.varsize() or else need to be pre-initialized such as

N = numel(zoom);
positionX = zeros(1, N);

because it is legal with codegen to make an array shorter (by assigning something smaller to it) but not to have it be variable sized without configuring it specially.

Answer 2

[JAI PRAKASH]

I just change

Line 12 with

zoom = zoom(zoom>0 & zoom<=6);
zoomMax = length(zoom);

And matlab coder shows no error, its working fine.. :)

Thanks for your comments