MATLAB中使用strjoin拼接含变量的字符串报错问题求助

Got it, let's break down why you're hitting this error and how to fix it right away.

Why the Error Happens #

The error message spells it out clearly: strjoin requires its first input to be either a string array or a cell array of character vectors (char type). Your problem is that the cell array {'rm', a} mixes two incompatible types:

• 'rm' is a standard character vector (char type)
• a is a string type (since you used string(i) in strcat, which outputs a string object)

Mixing these in the same cell array violates strjoin's input rules, hence the error.

Solution 1: Convert a to a Character Vector #

If you want to stick with a cell array, just convert your string variable a to a char using the char() function:

% Example with a sample value for i
i = 1;
a = strcat('file', string(i), '.mat');
a_char = char(a); % Convert string to char vector
command = strjoin({'rm', a_char});

Solution 2: Use a String Array Instead of a Cell Array #

MATLAB's string arrays are more intuitive for this kind of work. Wrap your elements in double quotes ("") to create a string array, which strjoin handles flawlessly:

i = 1;
a = strcat('file', string(i), '.mat');
command = strjoin(["rm", a]);

Bonus: A Cleaner String Splicing Method #

You don't even need strcat here—MATLAB lets you directly concatenate strings and numbers with the + operator, which is far more readable:

i = 1;
a = "file" + i + ".mat"; % Direct, clean string concatenation
command = strjoin(["rm", a]);

All these approaches will resolve the error and give you the joined string you need.

内容的提问来源于stack exchange，提问作者user3433489