TKCat (version 1.1.12)

dims.chMDB: Detailed information about the format of the tables

Description

Detailed information about the format of the tables

Usage

# S3 method for chMDB
dims(x, ...)
# S3 method for fileMDB
dims(
  x,
  ...,
  by = 1000,
  estimateThr = 5e+07,
  estimateSample = 10^6,
  showWarnings = TRUE
)
dims(x, ...)
# S3 method for memoMDB
dims(x, ...)
# S3 method for metaMDB
dims(x, ...)

Value

A tibble with one row for each considered table and the following columns:

• name: the name of the table

• format: "table", "matrix" or "MatrixMarket"

• ncol: number of columns

• nrow: number of rows

• records: number of records (nrow for tables and ncol*nrow for matrices)

• bytes: size in bytes

• transposed: FALSE by default. TRUE only for matrices stored in a transposed format.

Arguments

x

an object with embedded data tables

...

the name of the tables to consider (default: all of them)

by

the size of the batch: number of lines to count together (default: 1000)

estimateThr

file size threshold in bytes from which an estimation of row number should be computed instead of a precise count (default: 50000000 = 50MB)

estimateSample

number of values on which the estimation is based (default: 10^6)

showWarnings

a warning is raised by default if estimation is done.