"Undefined function or variable '****'. The first assignment to a local variable determines its class."

2012 5 23
6 个回答
回答已采纳
更新时间：2022 9 17
8 次查看（30 天）

1 个投票

Hi all,
I'm using Coder to convert my code to C/C++.When I attempt to convert one of my functions just for practice, i started receiving errors. I was unsure how to define my inputs, so I used stops and discovered my input was a struct. The fields in that input I was able to define mostly as double(1x1) (determined by using stops again) as well as one of the fields being a struct as well. Now the error I get when I tryto build my code is
Undefined function or variable 'DopplerSpread'. The first assignment to a local variable determines its class.
What am I doing wrong? Do I need to define each function prior to using it in my code? Below is a sample of the line of code receiving that error.
DopplerSpread(path_ct) = FadeAll.Subpaths(path_ct).DopplerSpread;

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 采纳的回答

Adam Kaas
Adam Kaas 2012-5-23

0 个投票

Since all of my "Undefined function or variable" errors were on variables, and all my variables were 1 x 1 doubles, I just defined them all as 0 prior to them being defined in a for loop. It seems you can not define them in a for loop.

更多回答（5 个）

Nam moon Kim
Nam moon Kim 2018-9-28
编辑：Nam moon Kim 2018-9-28

3 个投票

I had a same problem. I think that is variable initiation problem.
in the matlab, if there is not variable, that's variable auto generation. however, in the stateflow, need a initiation.
in my case
*********************** error **********************
function ~
for i=1:len
temp(i) = i;
end
end
*********************** not error ******************
function ~
temp = zeros(len,1);
for i=1:len
temp(i) = i;
end
end

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Nick
Nick 2021-7-9
Do you know what to do if the variable that is giving me an error is an input to the function and is needed in an if statement?

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Sana Ben Hmouda
Sana Ben Hmouda 2017-7-26

0 个投票

Hello everybody, The answer of Adam Kaas was very clear. Azza al-abri you need only to initialize the concerned variable at 0. (i.e if your variable is varia, so you put varia=0; before the loop starts)
Aaditya Umasankar
Aaditya Umasankar 2021-11-24

0 个投票

Hello everybody, in mining truck shovel operation,the truck takes some load from escavator to crusher(unloads) and come back to escavator to load and again unloads it at crusher,and this process continues till shift time ends so how do we loop the entity generator(number of trucks,truck capacity are enity attributes)) with enity server(escavator and crusher) , for this which type of block shall be used to solve the problem(simevents)

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