## How can you find the ascii value of a character?

This question arose after noticing that `num2str(x)` returns the ascii
character corresponding to the number `x`. The question is how to go
the other way. We know, for example, that `['0' 66]` results in the
string `0B`, thereby mapping the number `66` to the character
`B` but a more straightforward solution is to use `char(66)`
which returns `B`. For fun you can try the following:
>> x=32:1:126;
>> char(x)

The result is
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~

which shows all the printable ascii characters in order.
What is important about this question is *the procedure used to find
the answer*. What I did was the following:

- Realized that what we were looking for is something that appears to be
the inverse of
`num2str`.
- Guessed the inverse might be
`str2num`.
- Did
`help str2num`.
- This was not exactly what is called for because it only works on
ascii characters that represent numbers.
- At the bottom of the help page there is a
`see also` section.
- The function
`char` was listed there.
- Did
`help char`.
- Determined that is what is wanted.

The above procedure illustrates how you will learn more about MATLAB as you
use the tool. You will be coding and determine a need for a function. Then
you will need to check MATLAB for the existence of that function. Doing so
efficiently is, obviously, important.