matrix

#!/bin/bash
#****************************************************************************************************
# ** Author: WeiHao Kuang
# ** Email: kuangw@oregonstate.edu
# ** Description: This script is a matrix calculator and will perfrom simple mmatrix operations
#    dims, transpose, mean, addition, and multiplication 
#****************************************************************************************************

# References used:
# Canvas Assignment 1 Hints Section
# https://ss64.com/bash/wc.html
# https://www.cyberciti.biz/faq/bash-for-loop/
# https://ss64.com/bash/paste.html
# https://stackoverflow.com/questions/2439579/how-to-get-the-first-line-of-a-file-in-a-bash-script
# https://www.cyberciti.biz/faq/unix-for-loop-1-to-10/
# https://unix.stackexchange.com/questions/26601/how-to-read-from-two-input-files-using-while-loop

# this the trap that will remove files that are temp and are not useful after the program runs
# also this is used to delete the temp files in case there are program interupts, hangs, crashes etc.
trap "rm -f datafile* d2utmp* mtest* add* mdank* dank*;" QUIT KILL HUP INT TERM EXIT

# NAME:
# 	dims - gets the dimension for a matrix that is passed in
# SYNOPSIS:
#	dims matrix
# DESCRIPTION:
#	Prints "ROWS COLS" (Space separated!)

function dims () {

    datafilepath="datafile$$"   #variable holding tempfile path

    #handles input from stdin when there is no args with dims
    if [ $# = 0 ] 
    then
        if [ ! -t 0 ]   # if stdin not empty
        then 
            cat > "$datafilepath"

        else    #if stdin is empty
            printf "%s\n" "Incorrect # or args" 1>&2
            exit 1
        fi
    elif [ "$#" = 1 ]   #if there is 1 arg entered with dims
    then 
        datafilepath=$1     #datafilepath will get first argument
    fi

    #if argument count greater than 1, then error to stderr
    if [ $# -gt 1 ] 
    then 
        echo  "Error only one statement can be used!" 1>&2
        exit 1

    #if argument file is not readable error statment to stderr
    elif [ ! -r $1 ]
    then 
        echo "Not readable file!" 1>&2
        exit 1
    fi
    
    #row counting using cat and wc command on argument file passed in
    rows=$(cat $datafilepath | wc -l) 


    # uses the head command and row specifer to get
    # the columns of the in the line
    cols=$( head -n 1 $datafilepath | wc -w)
    echo -e "$rows $cols"
}

# NAME:
# 	transpose - transposes the matrix that is passed in
# SYNOPSIS:
#	transpose matrix
# DESCRIPTION:
#	Prints the transpose of the input, in a valid matrix format

function transpose () {

    if [ $# = 0 ] 
    then
        if [ ! -t 0 ]   # if stdin not empty
        then 
            cat > "$datafilepath"

        else    #if stdin is empty
            printf "%s\n" "Incorrect # or args" 1>&2
            exit 1
        fi
    elif [ "$#" = 1 ]   #if there is 1 arg entered with dims
    then 
        datafilepath=$1     #datafilepath will get first argument
    fi
    
    #checks to see if the arg count is > 1
    #if true then exit 1 with error statment to stderr
    if [ $# -gt 1 ] 
    then 
        echo "Incorrect arguments!" 1>&2
        exit 1
    
    #checks to see of the file passed in is readable
    #if not then exit 1 status, and error message to stderr
    elif [ ! -r $1 ]
    then 
        echo "File not readable!" 1>&2
        exit 1

    #runs the transpose on the passed in file
    else
        #gets the cols for passed in matrix
        cols=$( head -n 1 $datafilepath | wc -w)
        
        #for loop running cols amount of times
        for ((i=1;i<=$cols;i++)); 
        do 
            #cut is used to get the column
            #paste -s is used to get the column into a row
            cut -f$i $datafilepath | paste -s
        done
    fi
}

# NAME:
# 	mean - find the mean value of the matrix file passed in
# SYNOPSIS:
#	mean matrix
# DESCRIPTION:
#	Prints a row vector mean of the input matrix, matrix  
#   format with ***.5 values rounded away from zero

function mean () {
    if [ $# = 0 ] 
    then
        if [ ! -t 0 ]   # if stdin not empty
        then 
            cat > "$datafilepath"

        else    #if stdin is empty
            printf "%s\n" "Incorrect # or args" 1>&2
            exit 1
        fi
    elif [ "$#" = 1 ]   #if there is 1 arg entered with dims
    then 
        datafilepath=$1     #datafilepath will get first argument
    fi

    mtest="mtest$$" #process id in name for tempfile var

    if [ ! -r $datafilepath ] #if file is not readable
    then
        echo "File not readable!" 1>&2
        exit 1
    elif [ $# -gt 1 ] #if the argument count is > 1
    then
        echo "Incorrect arguments!" 1>&2
        exit 1
    else
        rows=$(cat $datafilepath | wc -l) #rows of the matrix
        cols=$(head -n 1 $datafilepath | wc -w) #cols of the matrix
        
        # for loop iterates the amount of cols in matrix
        for ((i=1;i<=$cols;i++))
        do
            cut -f$i $datafilepath > $mtest # cutted col goes to tempfile
            sum=0

            #while loop is used to read the tempfile line by line
            while read line
            do
                sum=$(( $line+$sum )) # gets the sum of the column
                
                # this will get the average of the column
                average=$(( ($sum + ($rows/2)*( ($sum>0)*2-1 )) / $rows ))    
            done < $mtest

            if [ $i -eq $cols ] # this will print the last cols with newline chars
            then
                printf "%s\n" $average
            else # otherwise that number that is printed will be tab delimited
                printf "%s\t" $average
            fi
        done
    fi 
}

# NAME:
# 	add - finds the added matrix from 2 input matrices
# SYNOPSIS:
#	mean matrix1 matrix2
# DESCRIPTION:
#	prints the sum, in a valid matrix format to stdout

function add () {

    #tempfiles with process ids in their names
    add_file1="add_file1$$"
    add_file2="add_file2$$"
    mtest1="mtest1$$"

    if [ $# -ne 2 ] # if the arg count ne 2
    then
        printf "%s\n" "Incorrect arguments!" 1>&2
        exit 1
    elif [ ! -r $1 ] || [ ! -r $2 ] # if the either file is not readable
    then
        printf "%s\n" "File/s not readable!" 1>&2
        exit 1
    else
        #obtaining the row and col infomation of the matrices m1 and m2
        rows1=$(cat $1 | wc -l) # cat to get rows1
        rows2=$(cat $2 | wc -l) # cat to get rows2
        cols1=$(head -n 1 $1 | wc -w) # using word count to get cols1
        cols2=$(head -n 1 $2 | wc -w) # using word count to get cols1

        # conditional to check the adding dimensions
        if [ $rows1 != $rows2 ] || [ $cols1 != $cols2 ]
        then
            printf "%s\n" "Matrix dimensions don't match!" 1>&2
        exit 1
        else
            # for loop runs cols1 times
            for ((i=1;i<=$cols1;i++))
            do
                # cutting the cols from m1 and m2
                # iterated by the for loop cols times
                cut -f$i $1 > $add_file1
                cut -f$i $2 > $add_file2

                counter=1
                # simultaneously reading bother add1 and add2
                while read theline1 <&3; read theline2  <&4;
                do
                    #adding the two number together from the column files
                    addition=$(( $theline1+$theline2 ))

                    #conditions are used to place the sums inside of a tempfile
                    if [ $counter = $rows1 ] #when the counter and rows are the same
                    then  
                        printf "%d%s\n" $addition >> $mtest1 # append to the tempfile
                    else
                        printf "%d%s\t" $addition >> $mtest1 # append to the tempfile
                    fi
                    ((counter++))
                done 3<$add_file1 4<$add_file2 # reading from tempfiles add_file1 and 2
            done

        # condionals below are used to determine the loop iterations
        # in the for loop in line 215
        iter=0
        if [ $cols1 -ne $rows1 ] 
        then
            iter=$rows1 # titeration variable
        else 
            iter=$cols1 # iteration variable
        fi

        # this for loop is used to display the summation matrix from the tempfiles
        for ((i=1;i<=$iter;i++)); 
        do 
            cut -f$i $mtest1 | paste -s # cut and paste to get to right format
        done
        fi 
    fi 
}

# NAME:
# 	multiply - finds the product matrix from 2 input matrices
# SYNOPSIS:
#	multiply matrix1 matrix2
# DESCRIPTION:
#	Prints a product matrix that is correct to the stdout

function multiply () {

    # tempfile with their process ids in the naming
    mdank="mdank$$"
    dankfile="dankfile$$"
    dankmemes="dankmemes$$"

    if [ $# -ne 2 ] # if the arg count not equal to 2
    then
        printf "%s\n" "Incorrect arguments!"
    elif [ ! -r $1 ] || [ ! -r $2 ] # if either file is not readable
    then
        printf "%s\n" "Incorrect arguments!"
    else
        #obtaining column and row information from m1 and m2
        rows1=$(cat $1 | wc -l)  # cat to get rows1
        rows2=$(cat $2 | wc -l)  # cat to get rows2
        cols1=$(head -n 1 $1 | wc -w) # using word count to get cols1
        cols2=$(head -n 1 $2 | wc -w) # using word count to get cols2

        # conditional checks to see if the matrix dimensions are compatible
        # such that: NxP * PxN
        if [ $cols1 -ne $rows2 ]
        then
            echo "Broken" 1>&2
            exit 1
        
        else # run the multipling code
            transpose $1 > $mdank #transposing the first inputted matrix

            #obtain column information from the transposed first matrix
            T_cols=$(head -n 1 $mdank | wc -w)

            # outter for loop used to iterate through the transposed matrix
            # columns
            for((i=1;i<=$T_cols;i++))
            do
                cut -f$i $mdank > $dankfile # cutting the transposed matrix into temp

                # 2nd for loop is used to iterate through the cols of the 2 matrix
                for((j=1;j<=$cols2;j++))
                do
                    sum_oproducts=0
                    cut -f$j $2 > $dankmemes # cutting cols from 2nd matrix

                    # while loop is used to read temp file simulatneously
                    #whilst multipling and adding them together
                    while read theline1 <&3; read theline2 <&4;
                    do
                        product_ans=$(( $theline1*$theline2 )) # multply rows and cols

                        # adding the products together
                        sum_oproducts=$(( $product_ans+$sum_oproducts )) 
                    done 3<$dankfile 4<$dankmemes

                    # condionals used to print out the matrix from var sum_products
                    if [ $j -eq $cols2 ]
                    then
                        printf "%s\n" $sum_oproducts
                    else
                        printf "%s\t" $sum_oproducts
                    fi

                done
            done
        fi
    fi
}
$1 "${@:2}"