SymbolInfoDouble HOW

Example from file: `examples/demos/lowlevel/01_general_operations.go`¶

The SymbolInfoDouble() method is used to get a single numeric property of a symbol. It requests a specific parameter specified in the Type field and returns its value in Value.

1️⃣ Getting current Bid price¶

bidReq := &pb.SymbolInfoDoubleRequest{
    Symbol: cfg.TestSymbol,
    Type:   pb.SymbolInfoDoubleProperty_SYMBOL_BID, // Current Bid price
}
bidData, err := account.SymbolInfoDouble(ctx, bidReq)
if err != nil {
    helpers.PrintShortError(err, "SymbolInfoDouble(BID) failed")
} else {
    fmt.Printf("  Bid price (SYMBOL_BID):        %.5f\n", bidData.Value)
}

🟢 Detailed Code Explanation¶

bidReq := &pb.SymbolInfoDoubleRequest{
    Symbol: cfg.TestSymbol,
    Type:   pb.SymbolInfoDoubleProperty_SYMBOL_BID,
}

Creates a SymbolInfoDoubleRequest request with two fields:

Symbol — instrument name, e.g. EURUSD, taken from appsettings.json → test_symbol.
Type — parameter type we want to get. In this case it's SYMBOL_BID — current Bid price.

bidData, err := account.SymbolInfoDouble(ctx, bidReq)

Calls the SymbolInfoDouble() method via gRPC.

ctx — execution context (manages timeout, cancellation, etc.);
bidReq — prepared request;
bidData — server response with the Value field where the required number is stored.

if err != nil {
    helpers.PrintShortError(err, "SymbolInfoDouble(BID) failed")
} else {
    fmt.Printf("  Bid price (SYMBOL_BID): %.5f\n", bidData.Value)
}

Checks for errors. If everything is successful — prints the value bidData.Value. Format %.5f outputs the number with 5 decimal places, as is customary for quotes.

Example result:

Bid price (SYMBOL_BID): 1.08540

📘 SYMBOL_BID — is the current bid price (Bid). It shows at what price you can sell the instrument at the moment.

2️⃣ Getting current Ask price¶

askReq := &pb.SymbolInfoDoubleRequest{
    Symbol: cfg.TestSymbol,
    Type:   pb.SymbolInfoDoubleProperty_SYMBOL_ASK, // Current Ask price
}
askData, err := account.SymbolInfoDouble(ctx, askReq)
if err != nil {
    helpers.PrintShortError(err, "SymbolInfoDouble(ASK) failed")
} else {
    fmt.Printf("  Ask price (SYMBOL_ASK):        %.5f\n", askData.Value)
}

📘 SYMBOL_ASK — current ask price (Ask). Shows at what price you can buy the instrument. Together with Bid, it forms the spread — the difference between buy and sell prices.

3️⃣ Getting point size (Point)¶

pointReq := &pb.SymbolInfoDoubleRequest{
    Symbol: cfg.TestSymbol,
    Type:   pb.SymbolInfoDoubleProperty_SYMBOL_POINT, // Point size
}
pointData, err := account.SymbolInfoDouble(ctx, pointReq)
if err != nil {
    helpers.PrintShortError(err, "SymbolInfoDouble(POINT) failed")
} else {
    fmt.Printf("  Point size (SYMBOL_POINT):     %.5f\n", pointData.Value)
}

📘 SYMBOL_POINT — minimum possible price change of the instrument (tick size). For currency pairs, this value determines quote precision. Examples: 0.00001 for EURUSD, 0.001 for USDJPY.

4️⃣ Getting minimum trade volume¶

volumeMinReq := &pb.SymbolInfoDoubleRequest{
    Symbol: cfg.TestSymbol,
    Type:   pb.SymbolInfoDoubleProperty_SYMBOL_VOLUME_MIN, // Minimum volume for trading
}
volumeMinData, err := account.SymbolInfoDouble(ctx, volumeMinReq)
if err != nil {
    helpers.PrintShortError(err, "SymbolInfoDouble(VOLUME_MIN) failed")
} else {
    fmt.Printf("  Min volume (VOLUME_MIN):       %.2f\n", volumeMinData.Value)
}

📘 SYMBOL_VOLUME_MIN — minimum allowed trading volume in lots. This parameter is set by the broker and determines whether trading is possible, for example, from 0.01 lot.

📦 What the server returns¶

After each SymbolInfoDouble() call, the gateway returns a simple protobuf structure with one field:

message SymbolInfoDoubleData {
  double Value = 1; // Value of the requested property
}

The Value field contains the numeric value of the parameter specified in the request (Type). Usually this is a quote, price step, volume, or other market indicator.

Below is a list of the most commonly used properties that can be requested via SymbolInfoDouble():

📘 All PropertyId enum values (SymbolInfoDoubleProperty)¶

Constant	Value	Description
`SYMBOL_BID`	0	Current Bid price
`SYMBOL_BIDHIGH`	1	Highest Bid of the day
`SYMBOL_BIDLOW`	2	Lowest Bid of the day
`SYMBOL_ASK`	3	Current Ask price
`SYMBOL_ASKHIGH`	4	Highest Ask of the day
`SYMBOL_ASKLOW`	5	Lowest Ask of the day
`SYMBOL_LAST`	6	Last deal price
`SYMBOL_LASTHIGH`	7	Highest Last price of the day
`SYMBOL_LASTLOW`	8	Lowest Last price of the day
`SYMBOL_VOLUME_REAL`	9	Last deal volume
`SYMBOL_VOLUMEHIGH_REAL`	10	Maximum volume of the day
`SYMBOL_VOLUMELOW_REAL`	11	Minimum volume of the day
`SYMBOL_OPTION_STRIKE`	12	Option strike price
`SYMBOL_POINT`	13	Point size (smallest price change)
`SYMBOL_TRADE_TICK_VALUE`	14	Tick value in account currency
`SYMBOL_TRADE_TICK_VALUE_PROFIT`	15	Tick value for profit position
`SYMBOL_TRADE_TICK_VALUE_LOSS`	16	Tick value for loss position
`SYMBOL_TRADE_TICK_SIZE`	17	Minimum price change
`SYMBOL_TRADE_CONTRACT_SIZE`	18	Contract size (lot size in base currency)
`SYMBOL_TRADE_ACCRUED_INTEREST`	19	Accrued interest
`SYMBOL_TRADE_FACE_VALUE`	20	Face value (for bonds)
`SYMBOL_TRADE_LIQUIDITY_RATE`	21	Liquidity rate
`SYMBOL_VOLUME_MIN`	22	Minimum volume for trading
`SYMBOL_VOLUME_MAX`	23	Maximum volume for trading
`SYMBOL_VOLUME_STEP`	24	Volume step (lot size increment)
`SYMBOL_VOLUME_LIMIT`	25	Maximum total volume of open positions
`SYMBOL_SWAP_LONG`	26	Swap for long positions
`SYMBOL_SWAP_SHORT`	27	Swap for short positions
`SYMBOL_SWAP_SUNDAY`	28	Triple swap day - Sunday
`SYMBOL_SWAP_MONDAY`	29	Triple swap day - Monday
`SYMBOL_SWAP_TUESDAY`	30	Triple swap day - Tuesday
`SYMBOL_SWAP_WEDNESDAY`	31	Triple swap day - Wednesday
`SYMBOL_SWAP_THURSDAY`	32	Triple swap day - Thursday
`SYMBOL_SWAP_FRIDAY`	33	Triple swap day - Friday
`SYMBOL_SWAP_SATURDAY`	34	Triple swap day - Saturday
`SYMBOL_MARGIN_INITIAL`	35	Initial margin
`SYMBOL_MARGIN_MAINTENANCE`	36	Maintenance margin
`SYMBOL_SESSION_VOLUME`	37	Summary volume of the current session
`SYMBOL_SESSION_TURNOVER`	38	Summary turnover of the current session
`SYMBOL_SESSION_INTEREST`	39	Summary open interest
`SYMBOL_SESSION_BUY_ORDERS_VOLUME`	40	Current volume of Buy orders
`SYMBOL_SESSION_SELL_ORDERS_VOLUME`	41	Current volume of Sell orders
`SYMBOL_SESSION_OPEN`	42	Open price of the current session
`SYMBOL_SESSION_CLOSE`	43	Close price of the current session
`SYMBOL_SESSION_AW`	44	Average weighted price of the current session
`SYMBOL_SESSION_PRICE_SETTLEMENT`	45	Settlement price of the current session
`SYMBOL_SESSION_PRICE_LIMIT_MIN`	46	Minimum price of the current session
`SYMBOL_SESSION_PRICE_LIMIT_MAX`	47	Maximum price of the current session
`SYMBOL_MARGIN_HEDGED`	48	Hedged margin
`SYMBOL_PRICE_CHANGE`	49	Change of price in %
`SYMBOL_PRICE_VOLATILITY`	50	Price volatility in %
`SYMBOL_PRICE_THEORETICAL`	51	Theoretical option price
`SYMBOL_PRICE_DELTA`	52	Option/warrant delta
`SYMBOL_PRICE_THETA`	53	Option/warrant theta
`SYMBOL_PRICE_GAMMA`	54	Option/warrant gamma
`SYMBOL_PRICE_VEGA`	55	Option/warrant vega
`SYMBOL_PRICE_RHO`	56	Option/warrant rho
`SYMBOL_PRICE_OMEGA`	57	Option/warrant omega
`SYMBOL_PRICE_SENSITIVITY`	58	Option/warrant sensitivity
`SYMBOL_COUNT`	59	Total number of properties (not used)

🧠 What it's used for¶

The SymbolInfoDouble() method is used:

to read market parameters without needing to request the entire SymbolInfo object;
in algorithms and strategies where you need to work with specific numeric values — for example, spread, price step, or tick value;
for validating trading conditions before an operation — check that volume is not less than VolumeMin, and the step matches VolumeStep;
for logging and demo examples, when you need to output individual symbol parameters to the console.

💬 In simple terms¶

SymbolInfoDouble() allows you to quickly get any numeric property of a symbol. Each request returns one value — Bid, Ask, Point, volume, etc. It's a lightweight and fast call, often used when working with code to read instrument parameters.