Data formats tell you what the data represents. Doubles are actually the best, commonly used, method to store signed numbers with amplitudes between 10^-300ish to 10^300ish.
It looks like you want to store or display the numeric values, as strings.
To store them, you can explicitly use sprintf, with the correct c-style string notation to return the values in a string format that has the correct amount of precision.
To display them you can explicitly use fprintf/sprintf, with the correct c-style string notation to return the values in a string format that has the correct amount of precision. Or, you can change matlab's default way of displaying numbers to "long" (though, that only handles up to 8 significant figures).
If you can't get the numbers into a string using those methods, in the format you want, you can, with the right intelligence, write a function to take a number and return it as you want.
