Use Sheets as a Calculator or Adding Machine

Changing the value in place based on a leading operator. Important Notes: * Since '+' is a legal operator to start a formula, Sheets automatically converts it to '=' * Using .splice() on e.value essentially forces it to be considered a String. Multiply it by 1 to force it to to be treated as a number for math. * Using the 'switch' logic is useful here since the operator will be one of a discreet set of options. Sheet (to copy) https://docs.google.com/spreadsheets/d/1DcO-9wRETypAen9XwtMEWNLhFOVCOZzDtFqC8DtB6rc/edit#gid=0 Script: function onEdit(e) { if (e.range.rowStart != 2 || e.range.columnStart != 1) return; let operator = e.value[0]; switch (operator){ case '=': e.range.setValue(1*e.oldValue+1*e.value.slice(1)); break; case '-': e.range.setValue(1*e.oldValue-1*e.value.slice(1)); break; case '*': e.range.setValue((1*e.oldValue)*(1*e.value.slice(1))); break; case '/': e.range.setValue((1*e.oldValue)/(1*e.value.slice(1))); break; default: e.range.setValue(e.oldValue); } } Connect with me: • [email protected] • spencerfarris.me • www.linkedin.com/in/spencer-farris/ • Twitter @FarrisSpencer • Google Product Expert support.google.com/docs/profile/12305