Convert number to string problem

I would like to ask if there is a way to output a number, which is stored as a variable, using simple commands, as shown in the following examples:

9 is converted to: 'The number is +9.'

6.54 is converted to: 'The number is +6.54.'

-7 is converted to: 'The number is -7.'

-9.2 is converted to: 'The number is -9.2.'

0 is converted to: 'The number is 0.'

I would like to display it in the command window and a message box (msgbox).

Please help. Thanks in advance.

[Alex Mcaulley]

What about str2double?

Answer 1

[madhan ravi]

number = 10; % an example
if number>=0
    sprintf('The number is : +%d',number)
else 
    sprintf('The number is : %d',number)
end

Assign a variable to sprintf() and then place it inside the command msgbox().

[Angus Wong]

Sorry, what is %d? Why it isn't %g?

[madhan ravi]

See https://in.mathworks.com/help/matlab/ref/sprintf.html#btf_bfy-1_sep_shared-formatSpec for more details adapt ehich suits you the best.

[Angus Wong]

If I want to display more than one numbers, such as:

a=9,b=8,c=0,d=-5,e=-6 (Not necceaasry in descending order.)

'The numbers are +9,+8, 0, -5 and -6 respectively.'

I have tried to do this, but its very long winded, and if there are 10 of them, it would get to thousands of lines. Any suggestions?

[Guillaume]

Well, the first problem is that you use a different variable for each number instead of putting them all into a single array.

If the numbers were stored in a single array, your question is trivially solved in many ways. One way:

numbers = [9, 8, 0, -5, -6];
fprintf('The numbers are %s respectively.\n', strjoin(compose('%+d', numbers), ', '));

[madhan ravi]

Thank you Guillaume, Stephen’s solution looks good but anyways let me give my suggestion too, use logical indexing group according to positive and negative numbers and use sprintf() all at once.

Answer 2

[Stephen23]

>> V = [9,8,0,-5,-6]; % your data should be in one array.
>> S = sprintf(', %+g',V(1:end-1));
>> S = sprintf('The numbers are%s and %+g respectively',S(2:end),V(end))
S = 'The numbers are +9, +8, +0, -5 and -6 respectively'
˜>> regexprep(S,'\+0([, ])','0$1') % if you don't like '+0'
ans = 'The numbers are +9, +8, 0, -5 and -6 respectively'