Coldbir API Examples

coldbir-api-examples.r

library(Coldbir)
a <- cdb(tempfile())
a[] <- mtcars
a[, 2012] <- mtcars
a[, 2013] <- mtcars
a[, c(2012,12)] <- mtcars
a[, c(2012,11)] <- mtcars

# DEFAULT: a[NULL, .all]

# vars: all, dims: all
a[]
a[, ]
a[NULL, ]
a[NULL, .all]
a[,.all]

# vars: all, dims: NULL
a[._]
a[._, ]
a[._, NULL]
a[.all]
a[.all, ]
a[.all, NULL]
a[,NULL]
a[NULL, NULL]

# vars: all, dims: 1 dim
a[, ._]
a[._, ._]
a[NULL, ._]
a[.all, ._]

# vars: all, dims: 2 dims
a[, c(._, ._)]
a[._, c(._, ._)]
a[NULL, c(._, ._)]
a[.all, c(._, ._)]

# vars: "qsec", dims: NULL
a["qsec", ]
a["qsec", NULL]

# vars: "qsec", dims: 1 dim
a["qsec", ._]

# vars: "qsec", dims: 2 dim
a["qsec", c(2012, ._)]
a["qsec", c(._, ._)]

# vars: "qsec", dims: all
a["qsec", .all]