Price and volume

The price of the first trade in the bar's interval. On a 5 minute NIFTY futures chart, the 09:15 bar's open is the first traded price of the session, which is why gap studies compare it with the previous bar's close.

open: series number

Type

series number

First value

bar 0

version 1
study("Opening gap", precision = 2)

gap = open - close[1]
plot(gap, "Gap from the previous close", gap >= 0 ? lime : red, style = "histogram")

Remarks. open is fixed once the bar's first trade prints, so a condition built only from open and older bars does not change while the bar forms.

See also. close, ohlc4, session.isFirstBar

The highest traded price in the bar's interval. On the forming bar it can only rise, and it is final once the bar is confirmed.

high: series number

Type

series number

First value

bar 0

version 1
study("Twenty bar high", overlay = true)

prevHigh = highest(high, 20)[1]
plot(prevHigh, "Highest high of the previous 20 bars", aqua, style = "step")
if close > prevHigh
    signal("BREAKOUT")

Remarks. Take the window's high from the previous bar, highest(high, 20)[1], when you test a breakout. The current bar's own high is always inside its own window, so close > highest(high, 20) can never be true.

See also. low, highest(), hl2

The lowest traded price in the bar's interval. On the forming bar it can only fall.

low: series number

Type

series number

First value

bar 0

version 1
study("Swing low stop", overlay = true)

stopLevel = lowest(low, 10)[1]
plot(stopLevel, "Lowest low of the previous 10 bars", red, style = "step")

See also. high, lowest(), hl2

The bar's closing price. On a bar that is still forming it is the latest traded price, so it moves up and down until the bar closes. It is the usual source for most indicators.

close: series number

Type

series number

First value

bar 0

version 1
study("Close and its mean", overlay = true)

plot(close, "Close", silver)
plot(sma(close, 20), "SMA 20", orange)

Remarks. close is the one name with two meanings. Read bare, it is this price. Written as a call, close() is the order that flattens a strategy's position, documented at close(). The compiler tells them apart by the brackets. In a study, close() is OS7001.

A condition on close can be true and then false within one forming bar. Signals, alerts and orders wait for the bar to close by default, so they act only on the final value. Read close[1] when you want a value that is already settled.

See also. open, hlc3, bar.isConfirmed

The quantity traded during the bar: shares for an NSE or BSE equity, contracts or units for a derivative. On the forming bar it grows with every trade.

volume: series number

Type

series number

First value

bar 0

version 1
study("Volume and its mean", format = "volume")

showVolume = chart.hasVolume != false     // true when the host says yes or says nothing
avgVolume = sma(volume, 20)
plot(showVolume ? volume : none, "Volume", close >= open ? fade(lime, 40) : fade(red, 40), style = "column")
plot(showVolume ? avgVolume : none, "20 bar mean", orange)

Remarks. volume is absent, not zero, on a bar for which the host supplies no volume. Zero is a real reading that means nobody traded; a volume nobody reported is a different fact. Anything computed from an absent volume is absent too, so a volume study draws a gap there rather than a flat line. Whether an index such as the NIFTY 50 arrives with no volume or with zeros depends on the data source, so use the futures contract when you need volume for an index.

chart.hasVolume says whether the host supplies volume at all, but a host may leave it unstated, and the /trading chart does in this release. That is why the example writes chart.hasVolume != false: it hides the volume only when the host says there is none.

See also. chart.hasVolume, vwap(), obv(), relativeVolume()

Open interest: the number of futures or options contracts outstanding at the end of the bar. It is what lets you read positioning on NFO and MCX contracts, which price and volume alone cannot show.

oi: series number

Type

series number

First value

bar 0

version 1
study("Open interest change", format = "volume")

oiChange = oi - oi[1]
plot(oiChange, "Change in open interest", oiChange >= 0 ? aqua : orange, style = "histogram")

Remarks. oi is absent where the host supplies no open interest, which is the normal case for a cash equity or an index, and then the example draws nothing. Open interest is a level at a moment, while volume is a flow over the bar, so when bars are combined into a coarser timeframe, the coarser bar's open interest is the last reading inside it, never the sum.

The classic reading: price rising with open interest rising suggests new positions being built, and price rising with open interest falling suggests existing short positions being closed.

See also. chart.hasOpenInterest, volume, change()

The bar's midpoint, (high + low) / 2. It ignores where the bar opened and closed, so it suits studies that care about the range, such as channel midlines.

hl2: series number

Type

series number

First value

bar 0

version 1
study("Midpoint trend", overlay = true)
plot(ema(hl2, 21), "EMA of the midpoint", aqua)

See also. hlc3, ohlc4, supertrend()

The typical price, (high + low + close) / 3. It is what vwap() averages by default and what cci() measures, and it is a steadier source than close alone.

hlc3: series number

Type

series number

First value

bar 0

version 1
study("Typical price mean", overlay = true)
plot(ema(hlc3, 21), "EMA of the typical price", orange)

See also. hl2, hlcc4, vwap()

The average of all four prices, (open + high + low + close) / 4. It smooths out a bar whose close landed at an extreme.

ohlc4: series number

Type

series number

First value

bar 0

version 1
study("Average price", overlay = true)
plot(sma(ohlc4, 10), "SMA of the average price", silver)

See also. hlc3, hlcc4

The close-weighted average, (high + low + close + close) / 4. It counts the close twice, so it follows the close more closely than hlc3 while still using the range.

hlcc4: series number

Type

series number

First value

bar 0

version 1
study("Close weighted mean", overlay = true)
plot(ema(hlcc4, 20), "EMA of the close weighted price", aqua)

See also. hlc3, ohlc4, close

The instant the bar opened, as a number of milliseconds since 1 January 1970 in UTC. Because it is an ordinary number, you can subtract two times to get an elapsed duration, compare a bar's time with a date you built, or store it to find a bar again later.

time: series number

Type

series number

First value

bar 0

version 1
study("Minutes since the day's first bar", precision = 0)

newDay = bar.isFirst or not date.isSameDay(time, time[1])
var dayStart = none
if newDay
    dayStart = time

plot((time - dayStart) / 60000, "Minutes since the day's first bar", aqua, style = "step")

Remarks. The number is the same everywhere; turning it into a date or a clock time depends on a timezone. The date functions read it in the chart's timezone by default, which is Asia/Kolkata on the /trading chart, so date.hour(time) of the first NSE bar is 9 and date.minute(time) is 15.

Store time, not bar.index, when you want to recognise a bar later. A bar index shifts when more history loads; a time does not.

See also. date.format(), date.hour(), chart.now(), session.isIn()