How to change the folder path in FOPEN for creating .dat file

Question

Halsey 2019-11-20

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/492081-how-to-change-the-folder-path-in-fopen-for-creating-dat-file

评论： Halsey 2019-11-21

i got an example code, but i dont understand how the path works.

fid= fopen(['.\result\norm\' algo '\' ActFunc_Hid '_' ActFunc_Out '\NOUT' num2str(nout) '.dat'], 'a'); %folder path
fprintf(fid, '\n \n');
fprintf(fid, '%s \n',algo);
fprintf(fid, '%s %s \n',ActFunc_Hid,ActFunc_Out);
fprintf(fid, '%s %s %s %s %s %s \n','nhid','repeat','TrainAcc','ValAcc','TestAcc','time');

assume algo: algorithm, ActFunc_Hid : hidden layer active function, ActFunc_Out : output layer active function, NOUT : neuron output, nhid is hidden neuron, etc

For 1, why does it start with a '.\' and what does those '_' and '\' in between mean?

Question: How to change the folder path?

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

Walter Roberson 2019-11-20

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/492081-how-to-change-the-folder-path-in-fopen-for-creating-dat-file#answer_402380

编辑：Walter Roberson 2019-11-21

在 MATLAB Online 中打开

Replace the first line with:

folder = fullfile('result', 'norm', algo, [ActFunc_Hid '_' ActFunct_Out]);
if ~exist(folder, 'dir')
    mkdir(folder);
end
filename = fullfile(folder, sprintf('NOUT%g.dat',nout));
fid = fopen(filename, 'a');

why does it start with a '.\'

In MS Windows, that means that you want to refer to something within the current folder.

and what does those '_' and '\' in between mean

The '_' is not special: it is just a literal underscore, used to separate the Hid value from the Out value so that they are easy to read and do not run together.

In MS Windows, the '\' is a directory seperator character, marking the end of a previous subdirectory name. After a '\' there can be another subdirectory name, but the last part can instead be a file name.

MacOS and Linux use '/' instead of '\', and it turns out that MS Windows can use '/' as well.

fullfile() knows how to use '\' or '/' as appropriate for the operating system being executed on.

4 个评论
显示 2更早的评论隐藏 2更早的评论

Walter Roberson 2019-11-21

Which is to say:

in any case where you would have a directory separator, use fullfile() instead
It is cleaner and more powerful to use sprintf('CONSTANT%format', value) rather than ['CONSTANT' num2str(value)]
When you are writing output files with directory names that are computed, then it is quite common that your target directories will not exist, so mkdir() is often recommended