Mean and Standard deviation


 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Mean and Standard deviation
# 1  
Old 04-27-2009
Java Mean and Standard deviation

Hi all,
I am new to shell scripting and wanna calculate the mean and standard deviation using shell programming.

I have a file with letters that are repeating and their corresponding duration
a 0.32
a 0.89
aa 0.34
aa 0.23
au 0.012
au 0.26
SIL 0.34
ai 0.9
b 0.29
bh 0.19
ssil 0.87

I want to calculate the mean and standard deviation for each letter. I am able to calculate for single letter, but cant do for whole date at a time.

grep -e '^a' file | grep -v 'aa'|grep -v 'ai'|grep -v 'au' > test.file
awk '{sum+=$2}END{print "Mean = ",sum/NR}' test.file

Thanks in advance.
# 2  
Old 04-27-2009
Check out this thread... does that help?
# 3  
Old 04-27-2009
Maybe the problem is in the regexp:

Quote:
Originally Posted by lakshmikanth.pg
grep -e '^a' file | grep -v 'aa'|grep -v 'ai'|grep -v 'au' > test.file
You obviously want to match "a", but not "aa" or "ai", etc., right? As your file has spaces delimiting the first field use these to limit your matched lines to only the wanted ones:

Code:
grep '^a ' file | ...

Notice the space character behind the "a" - this will match only the lines starting with "a" but not these starting with "a<something>".

I hope this helps.

bakunin
# 4  
Old 04-27-2009
those are not seperated by spaces, but with tabs like two columns
like seperating a from ai|au|aa , similarly their are b from bh
can u please help
# 5  
Old 04-27-2009
Quote:
Originally Posted by lakshmikanth.pg
those are not seperated by spaces, but with tabs like two columns
like seperating a from ai|au|aa , similarly their are b from bh
can u please help
Then replace the space by a tab character in my solution. It is possible to search for any character, you just have to take care that the shell doesn't devour the more fancy characters with a special meaning to it. This is what the single quotes around the regexp are for.

Replace in the following examples the "<tab>" with a literal tab character, i just write it that way to make it readable:

While this would not work as expected, because the shell would take the tab char:

Code:
echo "abc<tab>def" | grep c<tab>d

The following would work indeed:
Code:
echo "abc<tab>def" | grep 'c<tab>d'

Notice the difference: the quotation marks around the regexp.

I hope this helps.

bakunin
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

SMA (Single Moving Average) and Standard Deviation

Hello Team, I am using the following awk script to calculate the SMA (Single Moving Average) for an specific period but now I would like to include the standard deviation output. Could you please help me to modify this awk shell script awk -F, -v points=5 ' { a = $2; ... (4 Replies)
Discussion started by: csierra
4 Replies

2. Shell Programming and Scripting

Output mean and standard deviation of a row

I have a file that looks that this: 820 890 530 1650 1600 1800 1850 1900 2270 1640 2300 1670 2080 2200 2350 1150 1630 2210 I would like to output the mean and standard deviation of each row so that my final output would look like this 820 890 530 746.667 155.849 1650 1600 1800... (5 Replies)
Discussion started by: kayak
5 Replies

3. Shell Programming and Scripting

Computing average and standard deviation from multiple text files

Hello there, I found an elegant solution to computing average values from multiple text files awk '{for (i=1;i<=NF;i++){if ($i!~"n/a"){a+=$i}else{b++}}}END{for (i=1;i<=FNR;i++){for (j=1;j<=NF;j++){printf (a/(3-b))((b>0)?"~"b" ":" ")};printf "\n"}}' file1 file2 file3 I tried to modify... (2 Replies)
Discussion started by: charmmilein
2 Replies

4. Shell Programming and Scripting

calculating row-wise standard deviation using awk

Hi, I have a file containing 100,000 rows-by-120 columns and I need to compute for the standard deviation for each row. Any idea on how to calculate row-wise standard deviation using awk? My sample data looks like this: input data: 23 35 12 25 16 17 18 19 29 12 12 26 15 14 15 23 12 12... (2 Replies)
Discussion started by: ida1215
2 Replies

5. Shell Programming and Scripting

Finding standard deviation for all columns in a data file

Hi All, I want someone to modify the below script from this forum so that it can be used for all columns in the file( instead of only printing column 3 mean and standard deviation values). I don't know how to loop around all the columns. ... (3 Replies)
Discussion started by: ks_reddy
3 Replies

6. Shell Programming and Scripting

AWK script for standard deviation / root mean square deviation

I have a file with say 50 columns, each containing a whole lot of data. Each column contains data from a separate simulation, but each simulation is related to the data in the last (REFERENCE) column $50 I need to calculate the RMS deviation for each data line, i.e. column 1 relative to... (12 Replies)
Discussion started by: chrisjorg
12 Replies

7. Shell Programming and Scripting

Standard deviation in awk

Hi all, I need to find the standard deviation of each column of a dataset below for each hour. The data is given in 5 second intervals as shown below DATE TIME FRAC_DAYS_SINCE_JAN1 FRAC_HRS_SINCE_JAN1 EPOCH_TIME ... (11 Replies)
Discussion started by: gd9629
11 Replies

8. Shell Programming and Scripting

using awk to print average and standard deviation into a file

Hi I want to use awk to print avg and st deviation but it does not go into a file for column 1 only. I can do average and # of records but i cannot get st deviation. awk '{sum+=$1} END { print "Average = ",sum/NR}' thanks (1 Reply)
Discussion started by: phil_heath
1 Replies

9. UNIX for Dummies Questions & Answers

Calculating the Standard Deviation for a column

Hi all, I want to calculate the standard deviation for a column (happens to be column 3). Does any know of simple awk script to do this? Thanks (1 Reply)
Discussion started by: kylle345
1 Replies

10. Shell Programming and Scripting

Script for finding standard deviation

I have a CSV file that looks like 0,0,0,0,1,0,1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0 10,11,7,0,4,12,2,3,7,0,11,3,12,4,0,5,5,4,5,0,8,6,12,0,9,3,3,0,2,7,8 19,11,7,0,4,14,16,10,8,2,13,7,15,6,0,76,6,4,10,0,18,10,17,1,11,3,3,0,9,9,8... (7 Replies)
Discussion started by: RJ17
7 Replies
Login or Register to Ask a Question