A command line utility to display csv rows in a more human-readable format.
csv files often have these readability problems:
- csv files are hard to read because the columns don't always align.
- csv files with many columns are hard to read because the rows wrap around the screen.
One way to solve these problems is to display them vertically. For example, given the following csv file:
ID,FIRST_NAME,LAST_NAME,EMAIL,TEL
1001,John,Doe,[email protected],111-111-1111
1002,Jane,Smith,[email protected],222-222-2222
its vertical equivalent is:
ID : 1001
FIRST_NAME : John
LAST_NAME : Doe
EMAIL : [email protected]
TEL : 111-111-1111
ID : 1002
FIRST_NAME : Jane
LAST_NAME : Smith
EMAIL : [email protected]
TEL : 222-222-2222
csvread is such utility for displaying a csv file in a vertical format.
To display the csv file in vertical format, simply pass the filename to csvread:
$ csvread users.csv
ID : 1001
FIRST_NAME : John
LAST_NAME : Doe
EMAIL : [email protected]
TEL : 111-111-1111
ID : 1002
FIRST_NAME : Jane
LAST_NAME : Smith
EMAIL : [email protected]
TEL : 222-222-2222By default, csvread tries to guess the delimiter from the comma, tab, pipe, or
the SOH (ASCII 1) characters. To use another delimiter or to force a
delimiter, use the -d option.
For example, to force csvread to use the carrot (^) as the delimiter:
$ csvread -d^ users.rsv
ID : 1001
FIRST_NAME : John
LAST_NAME : Doe
EMAIL : [email protected]
TEL : 111-111-1111
ID : 1002
FIRST_NAME : Jane
LAST_NAME : Smith
EMAIL : [email protected]
TEL : 222-222-2222It is also possible to tell csvread to use an alternate set of characters from
which the guess a file's delimiter by setting the environment variable
CSV_DELIMS. For example, to tell csvread to guess delimiters from a comma
and a carrot in BASH:
$ export CSV_DELIMS=,^
$ csvread users.rsv
ID : 1001
FIRST_NAME : John
LAST_NAME : Doe
EMAIL : [email protected]
TEL : 111-111-1111
ID : 1002
FIRST_NAME : Jane
LAST_NAME : Smith
EMAIL : [email protected]
TEL : 222-222-2222csvread's output can be piped to cgrep to select records by its field value:
$ csvread users.csv | cgrep "^LAST_NAME *: Doe$"
ID : 1001
FIRST_NAME : John
LAST_NAME : Doe
EMAIL : [email protected]
TEL : 111-111-1111A plugin library may be specified to translate the values before they are output.
As an example, csvread provides a plugin to translate FIX messages. FIX
messages do not have headers, so use the -n option along with the -t option
to load the fix library that comes with csvmagic:
$ csvread -n -tfix fixmessages.csv... which takes the following content in fixmessages.csv:
8=FIX.4.2,35=D,49=CLIENT,56=BROKER,54=1,38=7000,55=AMZN,40=1
... to produces the following output:
8 BeginString : FIX.4.2
35 MsgType : D .. NewOrderSingle
49 SenderCompID : CLIENT
56 TargetCompID : BROKER
54 Side : 1 .. Buy
38 OrderQty : 7000
55 Symbol : AMZN
40 OrdType : 1 .. Market
You can also pass the full path to the library without the .py suffix, or set
the CSV_PLUGINS_PATH environment variable to the directory containing the
plugins.
NAME
csvread - print csv rows in a more human-readable format
SYNOPSIS
csvread [-d DELIM] [-f] [-g] [-m] [-n] [-s] [-t LIB] [FILE [FILE ...]]
DESCRIPTION
csvread displays a comma-separated value (csv) file FILE in a more readable format. It
prints one value per line, prefixed by the column name. An empty line is printed between
the records to serve as the record separator.
This purpose of this layout is to make it easier to associate each value with its column.
The layout can also be used to grep for a specific column or columns. Its output can be
piped to cgrep(1) to look for records containing a value in a specific column.
Options
-d DELIM, --delim=DELIM
Use DELIM as the value delimiter, where DELIM may be 'p' for the pipe (|), 't' for
the tab (\t), 'a' for the SOH (ASCII 1), or other string literal of one or more
characters and Python string escape sequences. DELIM may include escape charac-
ters. By default the delimiter is guessed from the characters in the CSV_DELIMS
environment variable.
-f, --diff-only
Show only the fields that differ between each row.
-g, --show-change
Show only the fields that differ between each row, and show how they changed.
-m, --multitable
The file may contain more than one csv table, divided by an empty line. The second
set of table is treated as though it were the start of a new csv file.
-n, --no-header
The file contains no header. The values are numbered by their column positions
instead.
-s, --strip-quotes
Strip quotes from field values.
-t LIB, --translator=LIB
Use the plugin library LIB to preprocess the values before display. LIB may be the
full path to the library without the .py suffix, or it may just be the library name
in which case CSV_PLUGINS_PATH is searched for the library.
Environment Variables
CSV_DELIMS
A set of characters used to guess the delimiter of a csv file. The guesswork hap-
pens when reading the first line of the first FILE, by testing each character
present in CSV_DELIMS for the character with the most occurrence in the line. If
any of the characters occur the same number of times (including zero), the earlier
character in the variable is chosen. If the environment variable is not set, it
defaults to ',\t|\x0001'. CSV_DELIMS may include escape characters.
CSV_PLUGINS_PATH
A colon-separated list of directories in which the plugin library is searched.
SEE ALSO
csvalign(1), csvcut(1), cgrep(1)