Regularizing numbers

If we need to read in numbers as strings, we have to worry about how they're formatted. However, we'll probably want the computer to deal with them as numbers, not as strings, and this can't happen if the string contains a comma or period to separate the thousands place. This allows the numbers to be sorted and to be available for mathematical functions.

In this recipe, we'll write a short function that takes a number string and returns the number. The function will strip out all of the extra punctuation inside the number and only leave the last separator. Hopefully, this will be the one that marks the decimal place.

Of course, the version of this function, which we'll see here, only works in locales that use commas to separate thousands and periods to separate decimals. However, it would be relatively easy to write versions that will work in any particular locale.

Getting ready

For this recipe, we're back to the most simple project.clj files...