Why does Matlab give me the entire string instead of just one element?

Hi, I'm trying to extract a value of a string, but if I type string(1) Matlab gives me the entire string.. How should I solve this?

Answer 1

[YT]

It would be usefull if you read the documentation on strings (and maybe also char)

mystring = "HelloWorld"; %notice double quotes
mychar = 'HelloWorld'; %notice single quotes

mystring(1)
%Output: HelloWorld

mychar(1)
%Output: H

string2char = char(mystring);
string2char(1)
%Output: H

As you can see you can easily make a char array from a string like this

[AelinAG]

Thanks for answering! Unfortunately I'm not allowed to use string2char(it is for a school assignment).

[YT]

string2char is just a (unfortunate) variable name to store the result of making a character array from your string (and not a build-in function). You could name it whatever, doesn't really matter.

[AelinAG]

Ah I understand, sorry, I'm new to programming! My string is a number that is given in the input of a function though, so how do I extract one of the elements of that number?

[YT]

Something like this then

input = "987654"; %input string
temp = char(input); %temporary variabele
output = temp(1) %will output '9' of type char

Answer 2

[ADragon]

I am guessing you might have a cell array instead of a string. What happens when you do this?

str = 'Hello Matlab';
str(1)

It should return 'H'. If you have a cell array it will return the whole string. For example:

c = {'Hello Matlab'};
c(1)

To get the first character use

c{1}(1)

which is first cell, first element of cell array c.

AD

[AelinAG]

Thanks for answering my question! Unfortunately, it still doesn't work :( Matlab returns: Brace indexing is not supported for variables of this type. My string is a number, maybe it has something to do with that?

[ADragon]

Can you post some code? You could possibly use num2str.

[AelinAG]

That's not allowed, it's for an assignment and we can't use num2str or str2num :(

[ADragon]

That stinks. Your teacher must be after something very specific. I would check docs for the functions that you CAN use. I'm not sure how to do what you are asking without functions.

[Walter Roberson]

Brace indexing is not supported for variables of this type

That establishes that your input is not a cell array of character vectors, and also establishes that your input is not a string object.

If your input were a character vector then using (1) to index it would have only returned a single character instead of the whole thing.

I therefore suspect that you are not being given a cell array or a character vector or a string object. I suspect that you are being passed a numeric object. What shows up if you ask for

class(NameOfVariableGoesHere)

?

Answer 3

[Image Analyst]

It's probably because string is a built-in function name. Use a different name for your variable. From the help for the string() function:

Description
example
str = string(A) converts the input array to a string array.

For example:

>> string(1)
ans = 
    "1"