fileio/

mg_read_ascii.pro

includes main-level program

Routines

top mg_read_ascii

result = mg_read_ascii(filename [, column_names=strarr] [, column_types=lonarr] [, comment_symbol=string] [, data_start=long] [, delimiter=string] [, groups=lonarr] [, missing_value=scalar] [, count=long] [, header=strarr] [, num_records=long] [, record_start=long] [, /verbose])

Wrapper to READ_ASCII and ASCII_TEMPLATE.

Return value

structure with field names given by COLUMN_NAMES keyword, or, if COLUMN_NAMES is not present, "col0", "col1", etc.

Parameters

filename in required type=string

filename of file to read

Keywords

column_names in optional type=strarr

names for the columns in the data; if there are groups specified, the column names should be repeated for each column in the group, so that the number of column names is always equal to the number of columns

column_types in optional type=lonarr

SIZE type codes for the columns in the data; if there are groups specified, the column types should be repeated for each column in the group, so that the number of column types is always equal to the number of columns

comment_symbol in optional type=string

specifies a comment character for the lines in the file

data_start in optional type=long default=0L

number of lines to skip at the beginning of the file

delimiter in optional type=string

delimiter between columns of data

groups in optional type=lonarr

indices of groups for each column, i.e.:

  [0, 0, 0, 0, 0, 0, 0]

indicates all seven columns are in a single group, where:

  [0, 1, 2, 3, 4, 5, 6]

would put each column in a new group

missing_value in optional type=scalar

value to use for missing items in the data

count out optional type=long

set to a named variable to get the number of records read

header out optional type=strarr

set to a named variable to get the header information skipped by DATA_START

num_records in optional type=long

number of records to read; default is to read all available records

record_start in optional type=long default=0

set to index of first record to read (after DATA_START is taken into account)

verbose in optional type=boolean

set to print runtime messages

Examples

Try the main-level example program at the end of this file:

  IDL> .run mg_read_ascii

It does:

  IDL> col_names = ['lon', 'lat', 'elev', 'temp', 'dewpt', 'wind_speed', 'wind_dir']
  IDL> wdata = mg_read_ascii(file_which('ascii.txt'), data_start=5, $
  IDL>                       column_types=[4, 4, 3, 3, 3, 3, 3], $
  IDL>                       column_names=col_names, $
  IDL>                       groups=lindgen(7))
  IDL> help, wdata
  ** Structure <2851608>, 7 tags, length=420, data length=420, refs=1:
     LON             FLOAT     Array[15]
     LAT             FLOAT     Array[15]
     ELEV            LONG      Array[15]
     TEMP            LONG      Array[15]
     DEWPT           LONG      Array[15]
     WIND_SPEED      LONG      Array[15]
     WIND_DIR        LONG      Array[15]

  IDL> adata = mg_read_ascii(file_which('ascii.dat'), data_start=3, $
  IDL>                       delimiter=string(9B), comment_symbol='%', $
  IDL>                       groups=lonarr(4), missing_value=-999.)
  IDL> print, adata.col0
        55.3000      22.1000      19.3000      40.0000
        19.1000     -999.000      15.1000      33.4000
        100.300      79.0000      22.1000      3.30000

File attributes

Modification date:	Wed May 14 15:07:14 2014
Lines:	68
Docformat:	rst rst

Personal library of Michael Galloy
Contact me if you have enhancement requests or bug fixes.

mglib

Personal IDL library for M. Galloy