Array indexing

Indexing out a time series is done with common bracketing semantics.

Row indexing

Example	Description	Indexing value
`[1]`	First row of data only	single integer
`[1:3]`	First through third row only	integer range
`[1:2:10]`	Odd row between first to tenth row	integer range with step
`[[1:3; 8]]`	First through third row and eight row	integer range & single integer
`[end]`	Last row

Examples in REPL:

using MarketData

ohlc[1]
ohlc[1:3]
ohlc[1:2:10]
ohlc[[1:3; 8]]
ohlc[end]

Example	Description	Indexing value
`[Date(2000, 1, 3)]`	The row containing Jan 3, 2000 timestamp	single Date
`[[Date(2000, 1, 3), Date(2000, 2, 4)]]`	The rows containing Jan 3 & Feb 4, 2000	multiple Dates
`[Date(2000, 1, 3):Day(1):Date(2000, 2, 4)]`	The rows between Jan 3, 2000 & Feb 4, 2000	range of Date

Examples in REPL:

using MarketData
using Dates

ohlc[Date(2000, 1, 3)]
ohlc[Date(2000, 1, 3):Day(1):Date(2000, 2, 4)]

Example	Description	Indexing value
`[:Open]`	The column named `:Open`	single symbol
`[:Open, :Close]`	The columns named `:Open` and `:Close`	multiple symbols
`[[:Open, :Close]]`	The columns named `:Open` and `:Close`	multiple symbols

Examples in REPL:

using MarketData
using Dates

ohlc[:Open]
ohlc[:Open, :Close]
cols = [:Open, :Close]
ohlc[cols]

Example	Description	Indexing value
`[1:3, :Open]`	`:Open` column & first 3 rows	single symbol & integer range
`[:Open][Date(2000, 1, 3)]`	`:Open` column and Jan 3, 2000	single symbol & Date

Examples in REPL:

using MarketData
using Dates

ohlc[1:3, :Open]
ohlc[:Open][Date(2000, 1, 3)]