The following functions can be used for
handling combinations of options, such as Straddles,
Strangles, Condors, Butterflies, etc. Option combos are mainly used for limiting
risk. For an introduction to options trading, see
The image below shows the profit or loss of an Iron Condor combo dependent of
the underlying price, at expiration (blue) and halfway to expiration (red).
Iron Condor payoff
combo (CONTRACT* C1, int N1, CONTRACT* C2, int N2, CONTRACT* C3, int N3,
CONTRACT* C4, int N4): int
Combines up to 4 option contracts C1..C4 to a combo. The number
and trade direction of contracts are given by N1..N4; use negative
numbers for selling and positive numbers for buying that contract, f.i.
-2 for short selling two contracts. Use 0 for not used contracts.
Returns the number of combo legs, i.e. the number of different contracts of the
combo. If any CONTRACT* pointer is zero, but the associated
number N is nonzero, it deletes the combo and returns 0. Source code in contract.c.
comboAdd (CONTRACT* C, int N): int
Adds a copy of the option contract C to the current combo. Amount
and trade direction of the contract is given by N; use a negative
number for selling and a positive number for buying. Returns the number of
the current combo leg. If C is 0, the function deletes all contracts from
the combo and returns 0.
comboLegs (): int
Returns the number of legs of the current combo that was defined before with
combo() or comboAdd() calls.
comboContract (int Leg): CONTRACT*
Pointer to the CONTRACT struct of the combo leg with the given
number (1..4). Macro defined in contract.c.
comboLeg (int Leg): int
Selects the contract of the combo leg with the given number (1..4), and returns
the number assigned to that contract as defined in the
combo() function. The number is negative for selling and positive for
buying, so it can be directly used for the Lots parameter
passed to enterLong.
comboStrike (int Leg): var
Returns the strike value of the given combo Leg (1..4).
Source code in contract.c.
comboRisk (int Type): var
Returns the maximum loss of the current short (Type == -1) or
long (Type == 1) combo. For combos with unlimited loss,
returns the loss when the price drops to zero or ends up at twice the strike,
whichever is worse. Type, fAsk, fBid,
and fStrike of all contracts must be set, so
contractPrice must have been called before; the other contract
parameters don't matter. Multiplier and transaction costs are not included. Source code in contract.c.
Returns the total premium of the current short (Type == -1) or
long (Type == 1) combo. Positive premium is earned, negative
premium is paid. fAsk and fBid of all
contracts must be set, so contractPrice must have
been called before; the other contract parameters don't matter. Multiplier
and Transaction costs are not included. Source code in contract.c.
||CONTRACT* pointer for leg 1..4, or 0 when the leg is not used
in the combo.
||Number of contracts for leg 1..4, negative for selling and positive for
buying contracts. 0 when the leg is not used in the combo.
||Number of the combo leg, 1..4, starting with 1
for the first contract.
- contract.c must be included for all above functions.
- Combo trades should be opened or closed in the order of legs, starting
with leg 1. They are then automatically combined to a combo order which is sent to the broker.
Many brokers offer reduced margin and commission on combos. The combo order
internally uses the SET_COMBO_LEG command, which must be
supported by the broker plugin. Otherwise the combo is split in separate
- Combos orders can take several minutes for being executed, even at
market. For this reason it is recommended to use GTC
orders and/or to increase the wait time with the
- The elements of the current combo can be accessed through the
ThisCombo pointer, defined in trading.h.
- Use the algo function for getting separate
- The script Payoff.c contains some definitions of
often used combos, such as spread, strangle, butterfly, condor. Call the
combo from the main function for plotting its profit/loss curve.
Example (see also Workshop 8 and Payoff.c):
0,0,0,0)) // Strangle combo
contract, contract variables,
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