Str2double gives NaN
显示 更早的评论
X = ["3.716,3.711,3.719,3.714,3.714,3.711,3.722,3.712,3.715,3.715,3.717,3.721,3.713,3.714,0.000"];
Y = str2double(X);
I am trying to convert the above string to double. However, using above code, the Y value is 'NaN'.
'str2num(X)' gives appropriate/required results.
Y = [3.71600000000000 3.71100000000000 3.71900000000000 3.71400000000000 3.71400000000000 3.71100000000000 3.72200000000000 3.71200000000000 3.71500000000000 3.71500000000000 3.71700000000000 3.72100000000000 3.71300000000000 3.71400000000000 0]
However, 'str2num' is not supported in code generation. Is there any alternative?
采纳的回答
X = "3.716,3.711,3.719,3.714,3.714,3.711,3.722,3.712,3.715,3.715,3.717,3.721,3.713,3.714,0.000";
str = X{1}; % character vector
idx = str==',';
idy = diff([true,idx,true]);
idb = find(idy<0);
ide = find(idy>0)-1;
num = numel(idb);
tmp = cell(num,1);
for k = 1:num
tmp{k} = str(idb(k):ide(k));
end
vec = str2double(tmp)
8 个评论
Praveen Kumar
2023-1-30
Praveen Kumar
2023-2-1
Steven Lord
2023-2-1
How is the X variable created in your application? If you're reading it in from a file there may be a way to have the function that imports the data automatically convert it to double instead of importing it as a string array.
Praveen Kumar
2023-2-2
编辑：Praveen Kumar
2023-2-2
The X variable is read from excel (.csv) file. Please find below screenshot of the original file opened in excel.
The CSV file is imported as output type 'table' which contains X and other variables (using readtable).
"The X variable is read from excel (.csv) file."
A CSV file is just a text file. CSV files exist completely independently from MS Excel.
"(using readtable)"
Probably you should fix the file importing, this is probably easier than fiddling around with text afterwards.
Please upload a sample data file by clicking on the paperclip button.
Praveen Kumar
2023-2-2
M = readmatrix('matlab_error_test.csv', 'Range',2, 'Delimiter',{',','"'}, 'ConsecutiveDelimitersRule','join')
X = M(:,2:16)
Praveen Kumar
2023-2-2
更多回答（2 个）
Askic V
2023-1-30
Try this:
X = "3.716,3.711,3.719,3.714,3.714,3.711,3.722,3.712,3.715,3.715,3.717,3.721,3.713,3.714,0.000";
newStr = split(X,',')
Y = str2double(newStr)
I would also like to suggest this solution:
X = "3.716,3.711,3.719,3.714,3.714,3.711,3.722,3.712,3.715,3.715,3.717,3.721,3.713,3.714,0.200";
f = strfind(X, ","); % find indices of delimiter
Y = zeros(1, numel(f)+1); % initialize output array
X_char = convertStringsToChars(X);
j = 1;
for i = 1:numel(f)
start = j;
Y(i) = str2double(X_char(j:f(i)-1));
j = f(i)+1;
end
Y(end) = str2double(X_char(f(i)+1:end)); % add last element
Y
类别
在 帮助中心 和 File Exchange 中查找有关 Data Type Conversion 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
