sh Linux.Bash.Numbers.Mathematics

Posted 2021-05-07

#!/bin/bash

trim () {
    str="$1"
    match="$2"
    # trim spaces by default
    if [ -z "$match" ]; then
        match=" "
    fi
    # trim leading
    while [ "${str:0:${#match}}" == "$match" ];
    do
        str="${str:${#match}:${#str}}"
    done
    # trim tailing
    while [ "${str:$((${#str}-${#match}))}" == "$match" ];
    do
        str="${str:0:$((${#str} - ${#match}))}" 
    done
    echo "$str"
}

#Remove leading and trailing spaces
example="    Hello     "
echo "`trim  "$example" " "`"

#The second parameter is optional when removing spaces
example="    Hello     "
echo "`trim  "$example"`"


#Remove leading and trailing occurences of "word"
example="wordHelloword"
echo "`trim  "$example" "word"`"

_float2fraction() { 
     [ -z "${1}" ] && return 1 
     _float2fraction__num="${1%%.*}" 
     _float2fraction__den="${1##*.}" 
     [ "${_float2fraction__num}" ] && [ "${_float2fraction__num}" -eq "0" ] && _float2fraction__num="" 
     _float2fraction__num="${_float2fraction__num}${_float2fraction__den}" 
     _float2fraction__zero="${#_float2fraction__den}" 
     _float2fraction__den="1" 
     #checking if denominator or numerator is greater 
     while [ "${_float2fraction__zero}" -gt "0" ]; do 
         _float2fraction__den="${_float2fraction__den}0" 
         _float2fraction__zero="$((${_float2fraction__zero}-1))" 
     done 
     if [ "${_float2fraction__num}" -gt "${_float2fraction__den}" ];then 
        _float2fraction__greater="${_float2fraction__num}" 
        _float2fraction__lower="${_float2fraction__den}" 
     else 
        _float2fraction__greater="${_float2fraction__den}" 
        _float2fraction__lower="${_float2fraction__num}" 
     fi #finding hcf 
     while [ "${_float2fraction__lower}" -ne "0" ];do 
         _float2fraction__hcf="${_float2fraction__lower}" 
         _float2fraction__lower=$((${_float2fraction__greater}%${_float2fraction__lower})) 
         _float2fraction__greater="${_float2fraction__hcf}" 
     done #dividing numerator and denominator by hcf 
     _float2fraction__num="$((${_float2fraction__num}/${_float2fraction__hcf}))" 
     _float2fraction__den="$((${_float2fraction__den}/${_float2fraction__hcf}))" #answer 
     printf "%s\\n" "${_float2fraction__num}/${_float2fraction__den}" 
 } 
 #==================================================== Example ==== 
 #_float2fraction "0.5"  #prints "1/2" 
 #_float2fraction "0.75" #prints "3/4" 
 #================================================================= 
 _float2fraction "0.5" 
 _float2fraction "0.75"

#!/bin/bash
 
# Find the greater from numbers given as arguments
 
FindGreater() {
  #FindGreater 0 1 0 2 3 444 333 100 0 0 
  local numbers=( "${@}" )              # Initialize the array with given arguments
  local lenght="${#numbers[@]}"         # Get the number of elem in array
  local num="0"
  while (( num < "${lenght}" )) ; do
 
    if [[ "${numbers[$num]}" -ge "${greater:-0}" ]] ; then
      local greater="${numbers[$num]}"
    fi
 
    ((num++))
  done
  echo "Greater is : \"${greater}\""
}

bash_factorial()
{
  # Function    : bash_factorial
  # Description : Calculates factorial up to counter
  # Input       : Counter, max factor
  # Output      : Factorial
  # Usage       : bash_factorial $x
  
  counter=$1
	factorial=1
	while [ $counter -gt 0 ]
	do
		factorial=$(($factorial * $counter))
		counter=$(( $counter - 1 ))
		done
		echo "The factorial is $factorial"
}
		
	

bash_sumofparts()
{
  # Function    : bash_sumofparts
  # Description : Calculates sum of integers up to counter
  # Input       : Counter
  # Output      : Sum of parts
  # Usage       : bash_sumofparts $x


  counter=$1
	sumofparts=0
	while [ $counter -gt 0 ]
	do
		sumofparts=$(($sumofparts + $counter))
		counter=$(( $counter - 1 ))
	done
	echo "The sumofparts is $sumofparts"
}		

1. bash_factorial                : Calculates facotiral up to counter
2. bash_sumofparts               : Calculates sum of parts up to counter
3. float_to_fraction             : Converts a float number into a fraction
4. _random()                     : Prints a random number between 2 limits
5. Find_Greater_Number           : Finds the greater number in the array
6. String_trim                   : Trims specified characters from a string
7. absolute_value                : Absolute value of a number

abs ()                           # Absolute value.
{                                # Caution: Max return value = 255.
  E_ARGERR=-999999

  if [ -z "$1" ]                 # Need arg passed.
  then
    return $E_ARGERR             # Obvious error value returned.
  fi

  if [ "$1" -ge 0 ]              # If non-negative,
  then                           #
    absval=$1                    # stays as-is.
  else                           # Otherwise,
    let "absval = (( 0 - $1 ))"  # change sign.
  fi  

  return $absval
}

_random() { #return a random number between two limits 
     #default to numbers between 1-10 
     _random__min="${1:-1}" 
     _random__max="${2:-10}" 
     _random__awk_prog='BEGIN {srand(); print int(MIN+rand()*(MAX-MIN+1))}' 
     awk -v MIN="${_random__min}" -v MAX="${_random__max}" "${_random__awk_prog}" < /dev/null 
} 
 #==================================================== Example ==== 
 printf "%s\\n" "$(_random)"     "prints random numbers between 1 and 10" 
 printf "%s\\n" "$(_random 1 5)" "prints random numbers between 1 and 5" 
 #=================================================================

616 _is_int() { #look for an integer, returns 0 on success, 1 otherwise 
617     #http://www.unix.com/shell-programming-and-scripting/172070-help-scripting-command.html 
618     case "${1}" in 
619         *[!0-9]*|"") return 1 ;; 
620     esac 
621 } 
622 #==================================================== Example ==== 
623 #printf "%s" "Enter input: " 
624 #read input 
625 #if ! _is_int "${input}" ; then 
626     #printf "%s\\n" "Your input must consist of only numbers." >&2 
627     #exit 1 
628 #else 
629     #printf "%s\\n" "Input is valid." 
630 #fi 
631 #exit 0 
632 #================================================================= 
633 

947 _seq() { #portable seq 
948     for _seq__arg; do 
949         case "${_seq__arg}" in 
950             *[!0-9-]*|"") return 1 ;; 
951         esac 
952     done 
953 
 
954     [ -z "${1}" ] && return 1 
955 
 
956     _seq__first="1"; _seq__increment="1"; _seq__last="${1}" 
957 
 
958     if [ "${#2}" -gt "0" ]; then 
959         _seq__first="${1}" 
960         _seq__last="${2}" 
961     fi 
962 
 
963     if [ "${#3}" -gt "0" ]; then 
964         _seq__first="${1}" 
965         _seq__increment="${2}" 
966         _seq__last="${3}" 
967     fi 
968 
 
969     while [ "$_seq__first" -le "${_seq__last}" ]; do 
970         printf "%s\\n" "${_seq__first}" 
971         _seq__first="$((_seq__first + _seq__increment))" 
972     done 
973 } 
974 #==================================================== Example ==== 
975 #_seq 3 
976 #1 
977 #2 
978 #3 
979 #================================================================= 
980