Convert matlab code to C code using matlab coder

Hi i've been trying to convert some code that reads excel files and manipulate them into C code using Matlab coder. I'm using some matlab functions like xlsread, dir, xlswrite. I've gotten errors like they are not supported and script is not supported. I know it's because the functions are not supported. How do i go about correcting this? My full code is below.

filename = dir('*xlsx');
filename = struct2cell(filename);
Maxsize=size(filename);

format long g;
for x=1:+1:Maxsize(1,2)
    for page=1:+1:3
data1=xlsread(char(filename(1,x)),page,'D5:D12');
data2=xlsread(char(filename(1,x)),page,'H5:H12');
data3=xlsread(char(filename(1,x)),page,'L5:L12');   
X=xlsread(char(filename(1,x)),page,'C15');

waferleftX=data1(1,1);
waferleftY=data1(2,1);

wafertopX=data2(1,1);
wafertopY=data2(2,1);

wafercenterX=data2(4,1);
wafercenterY=data2(5,1);

waferbotX=data2(7,1);
waferbotY=data2(8,1);

waferrightX=data3(1,1);
waferrightY=data3(2,1);

yoff=(wafertopY+waferbotY)/2;
xoff=(waferleftX+waferrightX)/2;

if (xoff>0)
newwaferleftX=waferleftX-abs(xoff);
newwaferrightX=waferrightX-abs(xoff);
newwafertopX=wafertopX-abs(xoff);
newwaferbotX=waferbotX-abs(xoff);
else 
newwaferleftX=waferleftX+abs(xoff);
newwaferrightX=waferrightX+abs(xoff);
newwafertopX=wafertopX+abs(xoff);
newwaferbotX=waferbotX+abs(xoff);

end

if (yoff>0)
newwafertopY=wafertopY-abs(yoff);
newwaferbotY=waferbotY-abs(yoff);
newwaferleftY=waferleftY-abs(yoff);
newwaferrightY=waferrightY-abs(yoff);
else 
newwafertopY=wafertopY+abs(yoff);
newwaferbotY=waferbotY+abs(yoff);
newwaferleftY=waferleftY+abs(yoff);
newwaferrightY=waferrightY+abs(yoff);

end

Y=(abs(newwaferleftY)+abs(newwaferrightY)+abs(newwafertopX)+abs(newwaferbotX))/4;
DeltaL=(abs(newwaferleftX)+abs(newwaferrightX)+abs(newwafertopY)+abs(newwaferbotY))/4;
theta=atan(Y/X);
Rotation=theta/0.000001;
Mag=DeltaL/X*1000000;

xlswrite(char(filename(1,x)),xoff,page,'K15');
xlswrite(char(filename(1,x)),yoff,page,'K16');

      end
  end

Answer 1

[Walter Roberson]

The supported external functions are a subset of the Standard C library. MATLAB Coder effectively only supports generating code that could be implemented in pure C on a system that had no operating system. Tasks such as xlswrite() are much too complex for direct support.

You will need to use something like coder.ceval() to call a third-party external library that can handle the creation or update of xlsx files.

[Jay Zhou]

Thanks for the reply. So what should i do with my code exactly?

[Walter Roberson]

See the examples

http://www.mathworks.com/help/simulink/slref/coder.ceval.html#zmw57dd0e168968

You will need to tell the code generator the data types of the arguments that your xlswrite function will expect. And you will need to write your own xlswrite C or C++ code or find someone's pre-written library.

If you are specifically targetting MS Windows then you could consider writing the code in terms of ActiveX / DCOM . See http://www.mathworks.com/matlabcentral/fileexchange/10465-xlswrite1

or if you are targetting a system that will have Java, see https://www.mathworks.com/matlabcentral/fileexchange/38591-xlwrite--generate-xls-x--files-without-excel-on-mac-linux-win

Have you consider the possibility of using csv files instead of xlsx files? csv files are much easier to output.