Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Pig, mail # user - Logarithm functions

Copy link to this message
Logarithm functions
Rajesh Srinivasan 2012-11-15, 03:31

Can you hep me with the syntax of the natural logarithm (base e) of an expression  in Pig? According to Help, the syntax is LOG(expression).

I am trying to basically perform the following query:

select server, processor, area, log(server_time)/log(2) as LogGroup, count(*) as users, sum(server_time) as group_time, sum(server_cnt) as group_cnt
from Table_reqd
group by 1, 2, 3, 4

My script is like:
L = LOAD '/user/RS/serverdata1030' AS (
--Group After loading data

A = group a by (server,processor,area,(double)LOG((server_time)+1) as LogGroup);

-- Generate Counts and Sums
B= foreach A generate group,(long) COUNT(reqd)as Users,(long) SUM(reqd.server_time)as time,(long) SUM(reqd.server_cnt)as count;

Store B into 'data';
The job fails and I get 'ERROR org.apache.pig.tools.grunt.GruntParser - ERROR 2244: Job failed, hadoop does not return any error message.'

I tried changing the datatypes etc but to no avail. Any thoughts on the correct syntax? Thanks.