单向双向：某些产品的手续费只在开仓时收取，有些则在开仓和平仓时都收取； The sensitivities method [2] includes initial calculating choice sensitivities called the Greeks due to the widespread practice of symbolizing the sensitivities employing Greek letters. On ne change rien à ce qui est en train de se passer, mais on modifie seulement son sens. En PNL, on distingue trois styles https://elliottxrksa.wikimidpoint.com/5157264/not_known_details_about_pnl