> To answer the original question, _sum can only sum numbers, it does > not understand numbers inside strings. >
The way I understood the OP's question was that he had correctly, following the error message, converted to using numbers instead of strings, but then didn't understand the obtained result. >> sidenote: super cool talk by Bartek Szopka about floating point numbers in >> JavaScript (and other languages) held at JSConf.eu 2013 >> >> https://www.youtube.com/watch?v=MqHDDtVYJRI This is interesting, nice. I come from a background where numerical precision and memory layout is often a concern (e.g. physics simulations, hardware readout), but these types of things I think can be more easily forgotten when using higher level languages like javascript, python, etc. Imo it's still an essential understanding to have.