Computing average values from multiple text files


 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Computing average values from multiple text files
# 1  
Old 07-29-2011
Computing average values from multiple text files

Hi,
first, I have searched in the forum for this, but I could not find the right answer. (There were some similar threads, but I was not sure how to adapt the ideas.)

Anyway, I have a quite natural problem: Given are several text files. All files contain the same number of lines and the same number of columns. I want to compute a file that contains at each cell (interpreting the files as tables) the average value of the corresponding cells from my files.

There is a problematic thing in the files: The cells may contain numbers or the string "n/a" which means something like "not computed". When some files have a "n/a" at some cell, then the result file should contain the average from the not-"n/a" values and (separated by some unique symbol like "~") the number of "n/a" values.

For example:
File 1
Code:
1 2   3
1 n/a 3

File 2
Code:
3 2   1
3 n/a 1

File 3
Code:
2 2 n/a
5 2 5

Now, want to compute the following:

Resultfile
Code:
2 2   2~1
3 2~2 3

Of course, I could implement this with some high-level programming language, but having this as script would make it much more comfortable in my application.

I think this should be easy for experts of awk or similar tools. Unfortunately I don't see an easy solution.

Thanks in advance.
# 2  
Old 07-29-2011
You have to specify the number of files in this code (marked red):
Code:
awk '{for (i=1;i<=NF;i++){if ($i!~"n/a"){a[FNR""i]+=$i}else{b[FNR""i]++}}}END{for (i=1;i<=FNR;i++){for (j=1;j<=NF;j++){printf (a[i""j]/(3-b[i""j]))((b[i""j]>0)?"~"b[i""j]" ":" ")};printf "\n"}}' file1 file2 file3

This User Gave Thanks to bartus11 For This Post:
# 3  
Old 07-29-2011
And another one:

Code:
awk 'END {
  for (i = 0; ++i <= fnr;) 
    for (j = 0; ++j <= nf;)    
      printf "%s", (((i, j) in na ? \
        (v[i, j] / ((ARGC - 1) - na[i, j]) "~" na[i, j]) : \
	  v[i, j]/(ARGC - 1)) (j < nf ? FS : RS))
	}
{
  for (i = 0; ++i <= NF;)
    $i ~ /n\/a/ ? na[FNR, i]++ : v[FNR, i] += $i
  # FNR/NF may not be available
  # in the END block with some
  # awk implementations
  # so I,m saving them here
  nf = NF; fnr = FNR
  }' file*

You may need to add division by zero attempted exception handler?
# 4  
Old 08-01-2011
Thanks

It works perfectly! Smilie
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

awk GSUB read field values from multiple text files

My program run without error. The problem I am having. The program isn't outputting field values with the column headers to file.txt. Each of the column headers in file.txt has no data. MEMSIZE SECOND SASFoundation Filename The output results in file.txt should show: ... (1 Reply)
Discussion started by: dellanicholson
1 Replies

2. Shell Programming and Scripting

Extracting values based on line-column numbers from multiple text files

Dear All, I have to solve the following problems with multiple tab-separated text file but I don't know how. Any help would be greatly appreciated. I have access to Linux mint (but not as a professional). I have multiple tab-delimited files with the following structure: file1: 1 44 2 ... (5 Replies)
Discussion started by: Bastami
5 Replies

3. Shell Programming and Scripting

Match first two columns and average third from multiple files

I have the following format of input from multiple files File 1 24.01 -81.01 1.0 24.02 -81.02 5.0 24.03 -81.03 0.0 File 2 24.01 -81.01 2.0 24.02 -81.02 -5.0 24.03 -81.03 10.0 I need to scan through the files and when the first 2 columns match I... (18 Replies)
Discussion started by: ncwxpanther
18 Replies

4. Shell Programming and Scripting

Read record from the text file contain multiple separated values & assign those values to variables

I have a file containing multiple values, some of them are pipe separated which are to be read as separate values and some of them are single value all are these need to store in variables. I need to read this file which is an input to my script Config.txt file name, first path, second... (7 Replies)
Discussion started by: ketanraut
7 Replies

5. UNIX for Dummies Questions & Answers

Computing for linearly-interpolated values using awk

Hi, I want to compute for linearly-interpolated values for my data using awk, any help is highly appreciated. How do I apply the linear interpolation formula to my data in awk given the equation below: x y 15 0 25 0.1633611 35 0.0741623 desired output: linear interpolation at... (4 Replies)
Discussion started by: ida1215
4 Replies

6. Shell Programming and Scripting

Average of a column in multiple files

I have several sequential files with name stat.1000, stat.1001....to stat.1020 with a format like this 0.01 1 3822 4.97379915032e-14 4.96982253992e-09 0 0.01 3822 1 4.97379915032e-14 4.96982253992e-09 0 0.01 2 502 0.00993165137406 993.165137406 0 0.01 502 2 0.00993165137406 993.165137406 0... (6 Replies)
Discussion started by: kayak
6 Replies

7. 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

8. UNIX Desktop Questions & Answers

How do you [e]grep for multiple values within multiple files?

Hi I'm sure there's a way to do this, but I ran out of caffeine/talent before getting the answer in a long winded alternate way (don't ask ;) ) The task I was trying to do was scan a directory of files and show only files that contained 3 values: I940 5433309 2181 I tried many variations... (4 Replies)
Discussion started by: callumw
4 Replies

9. Shell Programming and Scripting

Help in extracting multiple files and taking average at same time

Hi, I have 20 files which have respective 50 lines with different values. I would like to process each line of the 50 lines in these 20 files one at a time and do an average of 3rd field ($3) of these 20 files. This will be output to an output file. Instead of using join to generate whole... (8 Replies)
Discussion started by: ahjiefreak
8 Replies

10. Shell Programming and Scripting

Average of elements throught multiple files

Hi, I got a lot of files looking like this: 1 0.5 6 All together there are ard 1'000'000 lines in each of the ard 100 files. I want to build the average for every line, and write the result to a new file. The averaging should start at a specific line, here for example at line... (10 Replies)
Discussion started by: chillmaster
10 Replies
Login or Register to Ask a Question