get command return types

when I use the get command to return the contents of a textbox, using get(jObject, 'String')

i get something like 'abc', if my input was abc.

but when i just type in 'abc' in the command line, i get a return of abc (notice it does not have the quotation marks around it). My question is, how can i make it so that the contents i return from the textbox does not have those quotation marks around it, yet still a string type? Thanks

Answer 1

[Jan]

The variable returned from the get command is a cell string. It does not contain the quotes, but they appear only, if you display the cell string in the command window.

Example:

s = 'abc';
disp(s)
>> abc

c = {'abc'};
disp(c)
>>     'abc'

% Display the contents of the first cell element:
disp(c{1})
>> abc

The cell string is useful to store multiple lines of the "textbox" - I assume it is a UICONTROL('Style', 'edit'). Look for "cell string" in the documentation to learn more about this topic.

[Andy]

but the thing is when i have a list of them (i put the result from a bunch of textboxes in a cell, so i have a list), and then i compare it to if i enter those in manually (i.e. i enter into the code, not the command line), i get two different cell list, one with the quotation marks, and one without. This crashes my program because it requires comparison between two lists without the quotation marks. Thanks

[Andy]

when i try using the display command on my cell list, i get one with quotation marks

[Jan]

I do not understand. You have a list of what? What do you enter manually?

Again: The cell string does *not* have quotation marks. They are inserted just by the DISP command to allow for a distinction of {1} and {'1'}.

I assume you create a cell of cell strings. But this is pure guessing. It would be more clear if you post the relevant code and explain, what you want to achieve.

[Andy]

ok, i think i found out where the problem is, it is extracting the text boxes i want it to, but when i set another list as those variables from those list, it changes, when i say

list = mylist(1,1)

where list is the new list, and mylist is the list that i stored the variables from the text box in. both are type char, but list comes out with the apostrophe around them.

[Jan]

I still cannot follow. After "list = mylist(1,1)" list and mylist have the same type. Perhaps you wnat "mylist{1,1}" with curly braces?

Did you understand, that the quotes are not parts of the strings, but are shown only to increase the readability?

[Andy]

ok, if someone can explain what this error wants me to fix that be all i need...

???Error using ==>dataset.subsasgn at 1008

Value must be vector of class double

dataset.subsagn is a matlab inbuilt function. thanks

[Jan]

@Andy: I can only repeat: Please post the relevant part of the code. without seeing it, it is impossible to guess, what's going on.

Answer 2

[Andy]

so i have

if strcmp (filelist(i).name(1:3), namelist(1,1)) gasclopt = namelist(2,1);

so when i pass namelist(2,1) into gasclopt is different from when this:

if strcmp (filelist(i).name(1:3), namelist(1,1)) gasclopt = 'ESSO'

because the first one gives me an error later on in other function, while the later doesnt

[Jan]

What is the type of filelist? Perhaps you wnat "filelist{1}.name(1:3)"? Or is filelist comming from the DIR command? Then you would need: "{filelist(1:3).name}".

As I said already, try: "gasclopt = namelist{2,1};"

[Jan]

Using STCMP with a cell string replies a LOGICAL vector. Using vectors as condition in an IF statement inserts and ALL implicitely. It is safer to do this explicitely:

if all(strcmp(<cellstring>, <string>)) ...

[Andy]

when i do gasclopt = namelist{2,1}; it gives ???Conversion to char from cell is not possible

[Andy]

when i try filelist{1}.name(1:3), it says ???Cel contents reference from a non-cell array object

[Jan]

It would be easier to assist, if you explain the type of the data. The above errors are a result of the fact, that I can only guess the types.

Answer 3

[Andy]

when i do gasclopt = namelist{2,1}; it gives ???Conversion to char from cell is not possible

Answer 4

[Andy]

its fixed!

Answer 5

[Walter Roberson]

It is a bit complicated. The type of the value returned by get() of a String property depends upon how you set the string.

Read the descriptions of the various ways that the String property can be initialized for the various uicontrol Styles: http://www.mathworks.com/help/techdoc/ref/uicontrol_props.html#bqxoiqg

Now, if you initialized to a single string that (under the rules) would be interpreted as a single line, then get() of the String property will return a single line (i.e., a character row vector, also known as a string.)

If, though, you initialized to a padded array of strings, or if you initialized to a single string that contained '|' that (under the rules) were interpreted as line breaks, then get() of the String property will return a character array. (I do not recall at the moment whether I had found some exceptions that returned a cell array.)

If you initialized to a cell array of strings, then get() of the String property will return a cell array of strings.

Therefor, unless you are certain you know exactly how the String property was initialized, it is safest to test iscell() on the return value, and cellstr() if it was not already a cell.

[Jan]

Using CELLSTR in all cases is safe: It does not change the data if it is a cell string already.