OPT_SIMPLE_CHOOSER(call_put_flag,spot,strike,time1,time2,rate,cost_of_carry,volatility)
OPT_SIMPLE_CHOOSER models the theoretical price of simple chooser options.
call_put_flag is 'c' or 'p' to indicate whether the option is a call or a put.
spot is the spot price of the underlying asset.
strike is the strike price at which the option is struck.
time1 is the time in years until the holder chooses a put or a call option.
time2 is the time in years until the chosen option expires.
rate is the annualized risk-free rate of interest.
cost_of_carry is the leakage in value of the underlying asset, for common stocks, this would be the dividend yield.
OPT_BS, OPT_BS_DELTA, OPT_BS_RHO, OPT_BS_THETA, OPT_BS_GAMMA.