How to read array from a text file into each row of a matrix.

Question

Raghav Rathi 2022-2-26

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1659160-how-to-read-array-from-a-text-file-into-each-row-of-a-matrix

回答： Scott MacKenzie 2022-2-26

Hi,

I am trying to read a text file which contains arrays in each line. I am trying to read each line into new row of a matrix.

The text file is in the following format.

[255, 255, 0, 0, 11, 0, 1, 0, 11, 11, 11, 11, 11, 11]
[255, 255, 0, 0, 18, 0, 1, 0, 18, 18, 18, 18, 18, 18]
[255, 255, 0, 0, 12, 0, 1, 0, 12, 12, 12, 12, 12, 12]
[255, 255, 0, 0, 10, 0, 1, 9, 10, 218, 10, 138, 10, 58]
[255, 255, 0, 0, 4, 0, 1, 0, 4, 4, 4, 4, 4, 4]
.
.
.

I tried to do it using readmatrix but I am getting the following error.

Error using readmatrix (line 158)
Unable to find or open file. Check the path and
filename or file permissions.
Error in decodePyramid (line 9)
crc_ = readmatrix(dir+pktFile);

Any help is appreciated.

Thank you.

5 个评论
显示 3更早的评论隐藏 3更早的评论

Raghav Rathi 2022-2-26

在 MATLAB Online 中打开

Thanks Scott, It kind of works but It is also cutting the first and last element.

NaN 255 0 0 6 0 1 0 6 6 6 6 6 NaN

Can you help me with fixing that?

Raghav Rathi 2022-2-26

在 MATLAB Online 中打开

if you look at the text file, each line contains 14 elements

[255, 255, 0, 0, 6, 0, 1, 0, 6, 6, 6, 6, 6, 6]

But they way you mentioned is skipping the first and last elements.

NaN should be the '[' and ']' but there is a 225 and 6 missing as well.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Voss 2022-2-26

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1659160-how-to-read-array-from-a-text-file-into-each-row-of-a-matrix#answer_905270

在 MATLAB Online 中打开

input.txt

fid = fopen('input.txt');
data = str2num(fread(fid,'*char').');
fclose(fid);
disp(data);
   255   255     0     0    11     0     1     0    11    11    11    11    11    11
   255   255     0     0    18     0     1     0    18    18    18    18    18    18
   255   255     0     0    12     0     1     0    12    12    12    12    12    12
   255   255     0     0    10     0     1     9    10   218    10   138    10    58
   255   255     0     0     4     0     1     0     4     4     4     4     4     4

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

Scott MacKenzie 2022-2-26

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1659160-how-to-read-array-from-a-text-file-into-each-row-of-a-matrix#answer_905280

在 MATLAB Online 中打开

OK, this should work. First, combine dir and pktFile using the fullfile function. Read the data using readtable, then restore the 1st and last columns to numeric values (by removing the brackets and converting to double). If you want the data in a plain matrix, follow with table2array:

T = readtable(fullfile(dir, pktFile));
T.Var1 = cellfun(@(x) str2double(x), erase(T.Var1, '['));
T.Var14 = cellfun(@(x) str2double(x), erase(T.Var14, ']'));
crc_ = table2array(T);