detectImportOptions

Arguments

filename

path or name of file to read

format accepted: .txt, .dat and .csv

Name, Value

Name: 'Delimiter', Value: string: the column separator mark.

Name: 'Decimal', Value: string: the decimal mark, '.' or ','.

Name: 'NumHeaderLines', Value: double: the number of header lines.

opts

structure containing the following information:

variableNames	:	column names in the file.
variableTypes	:	data type of each column (double, string, datetime or duration).
inputFormat	:	data format. The detectImportOptions function tries to determine the input format for datetime and duration data. For others types, no format is to apply.
delimiter	:	the column seperator.
decimal	:	the decimal seperator.
datalines	:	contains the first and last line of file corresponding to data.
header	:	file header.
emptyCol	:	contains the number of empty columns.

Description

The detectImportOptions function determines several pieces of information from a file that are useful for reading. This function is used in the readtable and readtimeseries functions.

Examples

opts = detectImportOptions(filename)

Code = ["AF"; "NA"; "OC"; "AN"; "AS"; "EU"; "SA"];
NameContinent = ["Africa"; "North America"; "Oceania"; "Antarctica"; "Asia"; "Europe"; "South America"];
Area = [30065000; 24256000; 7687000; 13209000; 44579000; 9938000; 17819000]; // in km2
NumberCountry = [54; 23; 14; %nan; 47; 45; 12]; 
LifeExpectancy = [60; 78; 75; %nan; 72; 75; 74]; // in years

t = table(Code, NameContinent, Area, NumberCountry, LifeExpectancy, ...
    "VariableNames", ["Code", "NameContinent", "Area", "NumberCountry", "LifeExpectancy"])

// Write the table in CSV file
writetable(t, fullfile(TMPDIR, "data.csv"))

// DetectImportOptions
opts = detectImportOptions(fullfile(TMPDIR, "data.csv"))

r = readtable(fullfile(TMPDIR, "data.csv"), opts)

See also

• readtable — create a table from a file
• readtimeseries — create a timeseries from a file

History