How do you write a string in superscript?

For example, in finding a derivative of a single term, my code is as follows:

function derivative(cons,base,expo) 
%Finds the derivative of a single term. 
num = expo*cons; 
newExpo = expo-1;
deri = strcat(int2str(num),base^{'int2str(newExpo)'})

where I would like the "expo-1" value to be in superscript.

I have also tried:

deri = strcat(int2str(num),base^int2str(newExpo))
deri = strcat(int2str(num),'base^int2str(expo-1)')
deri = strcat(int2str(num),base^'int2str(expo-1)')

I would appreciate a general answer, as well as one specific to this problem, as I will likely need to know how to convert strings to superscript in general for later problems. Thank you in advance!

Answer 1

[Jan]

deri = strcat(int2str(num), 'base^{', int2str(newExpo), '}')

Or:

deri = sprintf('%dbase^{%d}', num, newExpo)

This is 1 command compared to the 3 commands with strcat and int2str. For scalar inputs I think the sprintf() approaches are always smarter.

[Kylie Hansen]

Is there a way to turn 'base' into a variable instead of a string that is included? For example, if someone calls the function with

derivative(1,x,2)

would it be possible for the input to be '2x^{1}'?

[Walter Roberson]

bname = inputname(base);
if isempty(bname); bname = 'x'; end     %if it was an expression
deri = sprintf('%d%s^{%d}', num, bname, newExpo)