Lookout is capable of converting text to numeric data automatically. For example, if you connect a TextEntry object to a Pot object and then enter a number into the TextEntry object that number will be displayed in the Pot. Depending on where your text is coming from, you might have to an intermediate Text object to retrieve the number out of the string using something like the MID function (take a look at the Lookout help for all of the text functions).
JR A.