string join does not work for char arrays?
조회 수: 28 (최근 30일)
이전 댓글 표시
I have a column list of numbers like the below
M = [2; 3; 5; 7; 16];
What I want is to create a string array like this
"2, 3, 5, 7, 16"
Why can't I use the below to get what I want? What is the correct way to do this?
b = join(num2str(M), ', ')
Here is the error:
"First argument must be a string array, character vector, or cell array of character vectors."
댓글 수: 0
채택된 답변
Star Strider
2020년 8월 28일
One approach:
M = [2; 3; 5; 7; 16];
M2Str = sprintf("%d, ",M(1:end-1)) + string(M(end))
producing:
M2Str =
"2, 3, 5, 7, 16"
.
댓글 수: 0
추가 답변 (3개)
Walter Roberson
2020년 8월 28일
strjoin(string(M),', ')
or
strjoin(cellstr(num2str(M)),', ')
You could also consider
num2str(M.', '%g, ')
but that will leave an extra trailing comma
Steven Lord
2020년 8월 28일
>> M = [2; 3; 5; 7; 16];
>> join(string(M), ", ")
ans =
"2, 3, 5, 7, 16"
num2str on M makes a char matrix which is not a "string array, character vector, or cell array of character vectors" and so is not a valid input to join. [Technically the error message should probably state 'character row vector', actually.]
Jeremy Perez
2020년 8월 28일
편집: Jeremy Perez
2020년 8월 28일
Hi Leon,
Type:
help num2str
> num2str: Convert numbers to character representation.
You're not using strings but character arrays, which are different datatypes in MATLAB.
Try not to use character arrays as much as possible when you mean to use strings.
You can use:
join(string(M), ', ')
strjoin(string(M), ', ')
You can also test this:
sprintf('%d, ', M)
It'll add a comma at the end of your string that you can remove but it's a very useful function.
참고 항목
카테고리
Help Center 및 File Exchange에서 Characters and Strings에 대해 자세히 알아보기
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!