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Calculate average using PIG

I am new to PIG and want to calculate the average of my single column, which looks like

0
10.1
20.1
30
40
50
60
70
80.1

I wrote this pig script

dividends = load 'myfile.txt' as (A);
dump dividends
grouped   = group dividends by A;
avg       = foreach grouped generate AVG(grouped.A);
dump avg

It analyzes the data as

(0)
(10.1)
(20.1)
(30)
(40)
(50)
(60)
(70)
(80.1)

but gives this error for the average

2013-03-04 15:10:58,289 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1200: Pig script failed to parse: 
<file try.pig, line 4, column 41> Invalid scalar projection: grouped
Details at logfile: /Users/PreetiGupta/Documents/CMPS290S/project/pig_1362438645642.log

ANY IDEA

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2 answers

AVG . group A, , , .

Pig GROUP ALL - , :

dividends = load 'myfile.txt' as (A);
dump dividends
grouped   = group dividends all;
avg       = foreach grouped generate AVG(dividends.A);
dump avg
+12

:

dividends = load 'myfile.txt' as (A);
grouped   = GROUP dividends all;
avg       = foreach grouped generate AVG(dividends);
dump avg
+3

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