How do I put spaces before a line in a txt file using strcat and fprintf?

28 次查看（过去 30 天）
Ali Almakhmari
Ali Almakhmari 2023-4-16
编辑： Image Analyst 2023-4-16
How do I put spaces before a line in a txt file using strcat and fprintf?
When I go in MATLAB and try to print ' 1,2,3' in the file opened in fid_wrt as shown below. I will find that the file has '1,2,3', without the spaces.
B{1} = '%.4f,%.4f,%.4f';
fprintf(fid_wrt,strcat(' \n',B{1},','),1:1:3);
I tried adding the spaces before \n...after it...nothing. I just can't get those spaces in the fid_wrt file. I just want those spaces before the numbers man. Whats weird is that fprintf (without writing in the file) does show those spaces in the command window!!

请先登录，再回答此问题。

采纳的回答

Stephen23
Stephen23 2023-4-16
STRCAT removes whitespace characters. The easy and robust approach is separate FPRINTF calls:
fprintf(fid_wrt,' \n')
fprintf(fid_wrt,B{1},1:1:3)
fprintf(fid_wrt,',')

更多回答（1 个）

Image Analyst
Image Analyst 2023-4-16
strcat does an automatic trim of spaces. Just use fprintf alone. No need for B or strcat.
% Have a line with spaces on it before the line with numbers on it.
fprintf(fid_wrt,' \n%.4f, %.4f, %.4f\n', 1 : 3);
  2 个评论
Ali Almakhmari
Ali Almakhmari 2023-4-16
The thing is, B{1} changes in the code...its not something that is a constant. So I need strcat to concatenate B{1} in the fprintf.
Image Analyst
Image Analyst 2023-4-16
编辑：Image Analyst 2023-4-16
You could put B in as a string
% Define a format specifier string using B.
B{1} = ' \n%.4f,%.4f,%.4f\n';
formatSpecifier = B{1};
% Have a line with spaces on it before the line with numbers on it.
fprintf(fid_wrt, formatSpecifier, 1 : 3);

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Characters and Strings 的更多信息

标签

产品


版本

R2021a

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by