codegen: Problems using a structure as an input parmeter

Question

AJ 2012-2-2

1
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/27854-codegen-problems-using-a-structure-as-an-input-parmeter

编辑： dpb 2013-10-1

I am developing a codegen project with multiple functions. One function BAR1 returns a structure of type FOO. Another function BAR2 accepts a structure of type FOO. However, the code generator creates two structures, indentical except they have different structure names. The code, as generated, produces a syntax error in my app:

FOO_TYPE foo;
double c;
foo = bar1();
c = bar2(foo);

error C2664: 'bar2' : cannot convert parameter 1 from 'FOO_TYPE' to 'const struct_T'

How can I make bar2() accept a struct of type 'FOO_TYPE' instead of internally generated type 'struct_T'?

A workaround is to use:

c = bar2(*(struct_T*)&foo);

but this is not robust if the structure name is redefined by codegen.

Thanks, AJ

Here is the Matlab code. In the codegen project, for bar2, I specified the input type "by example" using "FOO_TYPE". ====================

function foo = bar1
%bar1 - Code generator test case - Structure as an output
%#codegen
foo = FOO_TYPE;
foo.a = 1.0;
foo.b = 2.0;
====================  
function c = bar2(foo)
%bar2 - Code generator test case - Structure as an input
%#codegen
c = double(0);
c = sqrt(foo.a^2 + foo.b^2);
====================
function s = FOO_TYPE
%FOO_TYPE - Defines a structure
%#codegen
s = struct(...
  'a', double(0), ...
  'b', double(0));
coder.cstructname(s, 'FOO_TYPE');

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Fred Smith 2012-2-16

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/27854-codegen-problems-using-a-structure-as-an-input-parmeter#answer_37731

Hi AJ,

Have you looked at coder.cstructname? That command can be used to specify the C name to use for a structure type.

-Fred

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

Answer 2

Fred Smith 2012-2-3

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/27854-codegen-problems-using-a-structure-as-an-input-parmeter#answer_36244

Have you tried compiling both of these files with a single call to the codegen command? You can pass multiple entry points, and MATLAB Coder should ensure that the types are resolved correctly.

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

AJ 2012-2-6

Thanks for the reply.

I did build this project with a single codegen call with multiple entry points.

For defining input types, there seems to be no concept of "named structures". Structures are defined by only their fields. I was hoping there would be some codegen directive and/or method to assign names to input structures. I am not intimately familiar with coder, and have been replying on the user interfaces for project building.

AJ

请先登录，再进行评论。