MATH

Section: User Commands (1)
Updated: 1. April 1989
 

NAME

math - Simple mathematical summaries of a table  

SYNOPSIS

math [ < data ]  

DESCRIPTION

Math reads columnar data from the standard input and outputs a few summary statistics.

This is best explained by way of an example. Suppose the file data contains the lines:

x       y       z       v
-       -       -       -
0       1       2       3
1               3       4
2       3       4       5
3       4       5       6
4       5       6       7
where exactly one tab-character separates the columns (note that the second y-value is missing - denoted by two adjacent tabs).

The command math < data yields:

x       y       z       v       Type
-       -       -       -       ----
5       4       5       5       Freq
10      13      20      25      Sum
2       3       4       5       Mean
1.58114 1.70783 1.58114 1.58114 Stddev
4       5       6       7       Maximum
0       1       2       3       Minimum
on the standard output.

The output should be self-explanatory.  

SEE ALSO

reldb(1), compute(1).  

BUGS

Math assumes that two tabs in a row denotes a missing value. This is usually a correct assumption - an empty columns is normally a missing value and should not be counted or used in a sum.

Math only does simple checks for the number of digits appropriate for output. Sometimes this yields messy output, although most cases should be reasonable, as in the above example.

No checks for invalid data are made.