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Multiplication of two matrices

 
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# 8  
Old 02-22-2016
How about being able to select both the column to be printed in field 1 of the output, and the suffix of the fields to use for the calculations? Try
Code:
awk '
FNR == NR       {T[$1 SFX] = $3
                 next   
                }
                {printf "%s", $COL
                }
FNR == 1        {for (i=COL+1; i<=NF; i++)      {if ($i in T)   {C[++CNT] = i
                                                                 F[CNT] = T[$i]
                                                                 printf " %s", $i
                                                                }
                                                }
                 printf RS
                 next
                }
                {for (i=1; i<=CNT; i++) printf "%s%s", FS, $C[i] * F[i]
                 print ""
                }
' COL=2 SFX="_A" file2 file1
ID2 MI1_A MI2_A
1 0.4 -0.4
2 0.8 0

or
Code:
MI1_A MI1_H MI2_H
1 0 -0.2
2 0.4 -0.2

with COL=6 SFX="_H"
This User Gave Thanks to RudiC For This Post:
Akang
# 9  
Old 02-22-2016
@Don Cragun
In #Post5 i've tried to explain the files and what output i'm looking for. It is a bit confusing though, ill try to explain here
#File1:Headings from column6 onwards contain either "_A" or "_H" in the end. I only want to use the columns with "_A" for the desired multiplication. ID2 is the records id here and all other columns before column6 are not important.
#File2: Record id is the same as column id from column 6 onwards in File1 except for both "_A" and "_H".
Hope that helps to better understand the problem!

---------- Post updated at 09:06 AM ---------- Previous update was at 08:55 AM ----------

@RudiC: There is no output at all. Could you please explain your code a bit?

---------- Post updated at 09:08 AM ---------- Previous update was at 09:06 AM ----------

@RudiC: There is no output at all. Could you please explain your code a bit?
Last edited by Akang; 02-22-2016 at 08:05 PM..
# 10  
Old 02-23-2016
There is, as you can see, in the three lines under the code.

The FNR == NR part collects the factors from file2 into an array T, indexed by the field1 value suffixed by the parameter variable SFX.

Then, for every line in file1, the desired column is printed, identified by parameter variable COL.
For file1's first line, the to be selected columns are collected in array C, and the factors fromfile2 in array F, both indexed by a counter CNT. Also, the header fields are printed.

Then, for every input line, the desired fields, eventually multiplied by the respective factors, are printed.
# 11  
Old 02-24-2016
I dont' get any output when I run it :-(

---------- Post updated at 10:04 AM ---------- Previous update was at 09:56 AM ----------

I dont' get any output at all :-(

---------- Post updated at 04:59 PM ---------- Previous update was at 10:04 AM ----------

@RudiC: I think i am executing it wrong. Could you tell me how do i run this program?TIA!

---------- Post updated at 05:11 PM ---------- Previous update was at 04:59 PM ----------

@RudiC: I think i am executing it wrong. Could you tell me how do i run this program?TIA!
# 12  
Old 02-24-2016
Both code snippets provided work on the two files presented as samples in post#1 if run as shown. I don't think there are any version specific features used, so I can't imagine the scripts to fail unless
- you didn't run them as indicated (using the correct actual filenames!)
- your input files differ from the ones posted
# 13  
Old 02-24-2016
I did use the actual file names that i have. I saved this code to a file and saved it as code.awk, then in the shell promp i type :
Code:
awk code file2 file1 > output

. Is it the right way?
Moderator's Comments:
Mod Comment Please use CODE tags as required by forum rules.

I have guessed at what you typed into your shell, but with your punctuation I have no confidence that I have correctly guessed at how your post should have been formatted.
Last edited by Don Cragun; 02-24-2016 at 05:55 AM.. Reason: Add CODE and ICODE tags.
# 14  
Old 02-24-2016
Try copying the code from a post and paste it to the command line.
 
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