basically done

README

@@ -11,13 +11,13 @@ Dev Status
 ---
 Current Status
 -- addition 100% working
--- subtraction ~80% working
----- has major issues with decimal placement
----- I have no fix for this other than flat out long subtraction
--- multiplication ~50% working
----- has a lot of issues I need to look into
--- division ~80% working 
----- issues with decimal placement
+-- subtraction ~90% working
+---- decimal placement working now
+---- some numbers produce the wrong results... no idea why
+-- multiplication 100% working
+-- division ~90% working 
+---- may sometimes produce to many decimals
+---- rarely places decimals in wrong places
 ---
 Tester
 -- a tester is present at ./tester; it is ofc not pure sh as it compares with bc

division/div

@@ -116,4 +116,4 @@ ld() { # $1/$2
   echo "$o" # | $1/$2 | $dp | $do || $fd $1"
 }
 # 19 decimal points unless $3 is passed # bc uses 19
-[ "$1" -a "$2" ] && ld "$1" "$2" "${3:-19}"
+[ "$1" -a "$2" ] && ld "$1" "$2" "${3:-20}"

multiplication/mul

@@ -19,7 +19,7 @@ ad(){ # add decimal to $1 based on $2
     e="${m#$next}${e}"
     m="$next"; : $((n+=1))
   done
-  w="${1%$e}"; echo "${w:-0}.$e"
+  w="${1%$e}"; echo "${w:-0}.${e%0}"
 }
 [ -z "${1##*.*}" -o -z "${2##*.*}" ] || { # if not floats
   echo "$(($1*$2))"
@@ -27,16 +27,8 @@ ad(){ # add decimal to $1 based on $2
 }
 if [ ! -z "${1##*.*}" ]; then
   set -- "${1}.0" "$2"; d="${1#*.}"; d2="${2#*.}"
-  until [ "${#d}" -eq "${#d2}" ]; do
-    set -- "${1}0" "$2"
-    d="${1#*.}"
-  done
 elif [ ! -z "${2##*.*}" ]; then
   set -- "$1" "${2}.0"; d="${2#*.}"; d2="${1#*.}"
-  until [ "${#d}" -eq "${#d2}" ]; do
-    set -- "$1" "${2}0"
-    d="${2#*.}"
-  done
 fi # if $1/$2 is not a float; convert to float
 dn="$(countd $2 $(countd $1))"; m1="${1%.*}${1#*.}"; m2="${2%.*}${2#*.}"
 until [ "${m1#0}" = "$m1" ]; do
@@ -45,6 +37,8 @@ done
 until [ "${m2#0}" = "$m2" ]; do
   m2="${m2#0}"
 done # dash has issues when numbers have leading 0's
+
 # zsh,bash,etc don't need this at all
 # and really dash shouldn't either but /shrug
+#printf '%s\n%s\n' "${m1}*${m2}" "9223372036854775807"
 ad "$((m1*m2))" "$dn"

subtraction/sub

@@ -36,15 +36,11 @@ elif [ ! -z "${2##*.*}" ]; then
     d="${2#*.}"
   done
 fi # if $1/$2 is not a float; convert to float
-m1="${1%.*}"; m2="${2%.*}"; if [ "${#m2}" -gt "${#m1}" ]; then
-  dn="${#m2}"
-elif [ "${#m2}" -eq "${#m1}" ]; then
-  dn="${#m1}"
-else
-  dn="${#m1}"; : $((dn+=1))
-fi
-## SWAP IF $1 > $2; negative handling
 m1="${1%.*}${1#*.}"; m2="${2%.*}${2#*.}"
+dn=$((${1%.*}-${2%.*})); dn="${dn#-}"; dn="${#dn}"
+# decimal place is determined by the length of $1-$2
+# without decimals
+## SWAP IF $1 > $2; negative handling
 [ "$m1" -lt "$m2" ] && {
   set -- "$2" "$1"
   m1="${1%.*}${1#*.}"; m2="${2%.*}${2#*.}"; nr="-"

tester

@@ -13,32 +13,54 @@ fd() {
     : $((n+=1)); m="$next"
   done
 }
-for i in addition/add subtraction/sub multiplication/mul division/div; do
+ran() {
+  ran="$(${RPATH})"
+  ran="${ran#0.}"
+  until [ "${#ran}" -le 5 ]; do
+    ran="${ran%?}"
+  done
+  echo "${ran}"
+}
+case "$1" in
+  "") types="addition/add subtraction/sub multiplication/mul division/div" ;;
+  *) types="$1"
+esac
+IFS=" "; for i in ${types}; do
   for n in 1 2; do
-    ran="$(fd $(${RPATH}))"; : $((ran-=1)); until [ "$ran" -eq 1 -o "$ran" -eq 0 ]; do
-      ran="$(fd $(${RPATH}))"; : $((ran-=1))
+    ran="$(fd $(ran))"; : $((ran-=1)); until [ "$ran" -eq 1 -o "$ran" -eq 0 ]; do
+      ran="$(fd $(ran))"; : $((ran-=1))
     done
     case $ran in
-      0) ran=""; tn="$(${RPATH}).$(${RPATH}) $(${RPATH})";;
-      1) ran=""; tn="$(${RPATH}) $(${RPATH}).$(${RPATH})"
-         ran="$(fd $(${RPATH}))"; : $((ran-=1)); until [ "$ran" -eq 1 -o "$ran" -eq 0 ]; do
-           ran="$(fd $(${RPATH}))"; : $((ran-=1))
+      0) ran=""; tn="$(ran).$(ran) $(ran)";;
+      1) ran=""; tn="$(ran) $(ran).$(ran)"
+         ran="$(fd $(ran))"; : $((ran-=1)); until [ "$ran" -eq 1 -o "$ran" -eq 0 ]; do
+           ran="$(fd $(ran))"; : $((ran-=1))
          done
          case $ran in
-           1) ran=""; tn="${tn% *}.$(${RPATH}) ${tn#* }"
+           1) ran=""; tn="${tn% *}.$(ran) ${tn#* }"
          esac
     esac
     # use random number to determine if number will have decimal place
     case $i in
-      addition/add) op="+";;
-      subtraction/sub) op="-";;
-      multiplication/mul) op="*";;
-      division/div) op="/"
+      *addition/add) op="+";;
+      *subtraction/sub) op="-";;
+      *multiplication/mul) op="*";;
+      *division/div) op="/"
     esac
     aws="$(echo ${tn% *}${op}${tn#* } | bc -l)"; case "$(fd $aws)" in
       '.') aws="0${aws}"
     esac
     printf '  %s\n%s %s\n_____\nbc:  %s\n' "${tn% *}" "$op" "${tn#* }" "$aws"
-    printf 'psh: %s\n\n' "$(${i} ${tn% *} ${tn#* })"
+    oaws="$aws"; aws="${aws%.*}${aws#*.}"
+    [ "$aws" -ge 9223372036854775807 ] 2>/dev/null && {
+      printf 'psh: too large...\n\n'
+    } || printf 'psh: %s\n' "$(${i} ${tn% *} ${tn#* })"
+    [ "$oaws" = "$(${i} ${tn% *} ${tn#* })" ] && {
+      status=0
+    } || status=1
+    case "$status" in
+      0) printf 'Correct!\n\n' ;;
+      1) printf 'False..\n\n'
+    esac
   done
 done