Suffixation of decimal numbers

From Rosetta Code
Task
Suffixation of decimal numbers
You are encouraged to solve this task according to the task description, using any language you may know.

Suffixation:   a letter or a group of letters added to the end of a word to change its meaning.

      ─────   or, as used herein   ─────

Suffixation:   the addition of a metric or "binary" metric suffix to a number, with/without rounding.


Task

Write a function(s) to append (if possible)   a metric   or   a "binary" metric   suffix to a number   (displayed in decimal).

The number may be rounded   (as per user specification)   (via shortening of the number when the number of digits past the decimal point are to be used).


Task requirements
  •   write a function (or functions) to add   (if possible)   a suffix to a number
  •   the function(s) should be able to express the number (possibly with a suffix) in as many decimal digits as specified
  •   the sign should be preserved   (if present)
  •   the number may have commas within the number   (the commas need not be preserved)
  •   the number may have a decimal point and/or an exponent as in:   -123.7e-01
  •   the suffix that might be appended should be in uppercase;   however, the   i   should be in lowercase
  •   support:
  •   the metric suffixes:   K M G T P E Z Y X W V U
  •   the "binary" metric suffixes:   Ki Mi Gi Ti Pi Ei Zi Yi Xi Wi Vi Ui
  •   the (full name) suffix:   googol   (lowercase)   (equal to 1e100)     (optional)
  •   a number of decimal digits past the decimal point   (with rounding).   The default is to display all significant digits
  •   validation of the (supplied/specified) arguments is optional but recommended
  •   display   (with identifying text):
  •   the original number   (with identifying text)
  •   the number of digits past the decimal point being used   (or none, if not specified)
  •   the type of suffix being used   (metric or "binary" metric)
  •   the (new) number with the appropriate   (if any)   suffix
  •   all output here on this page


Metric suffixes to be supported   (whether or not they're officially sanctioned)
     K     multiply the number by  10^3              kilo      (1,000)
     M     multiply the number by  10^6              mega      (1,000,000)
     G     multiply the number by  10^9              giga      (1,000,000,000)
     T     multiply the number by  10^12             tera      (1,000,000,000,000)
     P     multiply the number by  10^15             peta      (1,000,000,000,000,000)
     E     multiply the number by  10^18             exa       (1,000,000,000,000,000,000)
     Z     multiply the number by  10^21             zetta     (1,000,000,000,000,000,000,000)
     Y     multiply the number by  10^24             yotta     (1,000,000,000,000,000,000,000,000)
     X     multiply the number by  10^27             xenta     (1,000,000,000,000,000,000,000,000,000)
     W     multiply the number by  10^30             wekta     (1,000,000,000,000,000,000,000,000,000,000)
     V     multiply the number by  10^33             vendeka   (1,000,000,000,000,000,000,000,000,000,000,000)
     U     multiply the number by  10^36             udekta    (1,000,000,000,000,000,000,000,000,000,000,000,000)


"Binary" suffixes to be supported   (whether or not they're officially sanctioned)
     Ki    multiply the number by  2^10              kibi      (1,024)
     Mi    multiply the number by  2^20              mebi      (1,048,576)
     Gi    multiply the number by  2^30              gibi      (1,073,741,824)
     Ti    multiply the number by  2^40              tebi      (1,099,571,627,776)
     Pi    multiply the number by  2^50              pebi      (1,125,899,906,884,629)
     Ei    multiply the number by  2^60              exbi      (1,152,921,504,606,846,976)
     Zi    multiply the number by  2^70              zeb1      (1,180,591,620,717,411,303,424)
     Yi    multiply the number by  2^80              yobi      (1,208,925,819,614,629,174,706,176)
     Xi    multiply the number by  2^90              xebi      (1,237,940,039,285,380,274,899,124,224)
     Wi    multiply the number by  2^100             webi      (1,267,650,600,228,229,401,496,703,205,376)
     Vi    multiply the number by  2^110             vebi      (1,298,074,214,633,706,907,132,624,082,305,024)
     Ui    multiply the number by  2^120             uebi      (1,329,227,995,784,915,872,903,807,060,280,344,576)


For instance, with this pseudo─code
                                 /* 1st arg: the number to be transformed.*/
                                 /* 2nd arg: # digits past the dec. point.*/
                                 /* 3rd arg: the type of suffix to use.   */
                                 /*         2   indicates "binary" suffix.*/
                                 /*        10   indicates  decimal suffix.*/
     a = '456,789,100,000,000'   /* "A"  has  eight  trailing zeros.      */
     say ' aa=' suffize(a)       /* Display a suffized number to terminal.*/
                                 /* The  "1"   below shows one decimal ···*/
                                 /*         digit past the decimal point. */
     n = suffize(a, 1)           /* SUFFIZE  is the function name.        */
     n = suffize(a, 1, 10)       /* (identical to the above statement.)   */
     say '  n=' n                /* Display value of  N  to terminal.     */
                                 /* Note the rounding that occurs.        */
     f = suffize(a, 1,  2)       /* SUFFIZE  with one fractional digit    */
     say '  f=' f                /* Display value of  F  to terminal.     */
                                 /* Display value in "binary" metric.     */
     bin = suffize(a, 5, 2)      /* SUFFIZE with binary metric suffix.    */
     say 'bin=' bin              /* Display value of  BIN  to terminal.   */
     win = suffize(a, 0, 2)      /* SUFFIZE with binary metric suffix.    */
     say 'win=' win              /* Display value of  WIN  to terminal.   */
     xvi = ' +16777216 '         /* this used to be a big computer ···    */
     big = suffize(xvi, , 2)     /* SUFFIZE with binary metric suffix.    */
     say 'big=' big              /* Display value of  BIG  to terminal.   */

would display:

      aa= 456.7891T
       n= 456.8T
       f= 415.4Ti
     bin= 415.44727Ti
     win= 415Ti
     big= 16Mi


Use these test cases
               87,654,321
              -998,877,665,544,332,211,000      3
              +112,233                          0
               16,777,216                       1
               456,789,100,000,000              2
               456,789,100,000,000              2      10
               456,789,100,000,000              5       2
               456,789,100,000.000e+00          0      10
              +16777216                         ,       2
               1.2e101
               (your primary disk free space)   1                  ◄■■■■■■■ optional


Use whatever parameterizing your computer language supports,   and it's permitted to create as many separate functions as are needed   (if needed)   if   function arguments aren't allowed to be omitted or varied.


Related tasks



Go

As go doesn't support either function overloading or optional arguments, we just pass a single string to the suffize function and then split out what we need. <lang go>package main

import (

   "fmt"
   "math/big"
   "strconv"
   "strings"

)

var suffixes = " KMGTPEZYXWVU" var ggl = googol()

func googol() *big.Float {

   g1 := new(big.Float).SetPrec(500)
   g1.SetInt64(10000000000)
   g := new(big.Float)
   g.Set(g1)
   for i := 2; i <= 10; i++ {
       g.Mul(g, g1)
   }
   return g

}

func suffize(arg string) {

   fields := strings.Fields(arg)
   a := fields[0]
   if a == "" {
       a = "0"
   }
   var places, base int
   var frac, radix string
   switch len(fields) {
   case 1:
       places = -1
       base = 10
   case 2:
       places, _ = strconv.Atoi(fields[1])
       base = 10
       frac = strconv.Itoa(places)
   case 3:
       if fields[1] == "," {
           places = 0
           frac = ","
       } else {
           places, _ = strconv.Atoi(fields[1])
           frac = strconv.Itoa(places)
       }
       base, _ = strconv.Atoi(fields[2])
       if base != 2 && base != 10 {
           base = 10
       }
       radix = strconv.Itoa(base)
   }
   a = strings.Replace(a, ",", "", -1) // get rid of any commas
   sign := ""
   if a[0] == '+' || a[0] == '-' {
       sign = string(a[0])
       a = a[1:] // remove any sign after storing it
   }
   b := new(big.Float).SetPrec(500)
   d := new(big.Float).SetPrec(500)
   b.SetString(a)
   g := false
   if b.Cmp(ggl) >= 0 {
       g = true
   }
   if !g && base == 2 {
       d.SetUint64(1024)
   } else if !g && base == 10 {
       d.SetUint64(1000)
   } else {
       d.Set(ggl)
   }
   c := 0
   for b.Cmp(d) >= 0 && c < 12 { // allow b >= 1K if c would otherwise exceed 12
       b.Quo(b, d)
       c++
   }
   var suffix string
   if !g {
       suffix = string(suffixes[c])
   } else {
       suffix = "googol"
   }
   if base == 2 {
       suffix += "i"
   }
   fmt.Println("   input number =", fields[0])
   fmt.Println("  fraction digs =", frac)
   fmt.Println("specified radix =", radix)
   fmt.Print("     new number = ")
   if places >= 0 {
       fmt.Printf("%s%.*f%s\n", sign, places, b, suffix)
   } else {
       fmt.Printf("%s%s%s\n", sign, b.Text('g', 50), suffix)
   }
   fmt.Println()

}

func main() {

   tests := []string{
       "87,654,321",
       "-998,877,665,544,332,211,000      3",
       "+112,233                          0",
       "16,777,216                        1",
       "456,789,100,000,000",
       "456,789,100,000,000               2      10",
       "456,789,100,000,000               5       2",
       "456,789,100,000.000e+00           0      10",
       "+16777216                         ,       2",
       "1.2e101",
       "446,835,273,728                   1",
       "1e36",
       "1e39", // there isn't a big enough suffix for this one but it's less than googol
   }
   for _, test := range tests {
       suffize(test)
   }

}</lang>

Output:
   input number = 87,654,321
  fraction digs = 
specified radix = 
     new number = 87.654321M

   input number = -998,877,665,544,332,211,000
  fraction digs = 3
specified radix = 
     new number = -998.878E

   input number = +112,233
  fraction digs = 0
specified radix = 
     new number = +112K

   input number = 16,777,216
  fraction digs = 1
specified radix = 
     new number = 16.8M

   input number = 456,789,100,000,000
  fraction digs = 
specified radix = 
     new number = 456.7891T

   input number = 456,789,100,000,000
  fraction digs = 2
specified radix = 10
     new number = 456.79T

   input number = 456,789,100,000,000
  fraction digs = 5
specified radix = 2
     new number = 415.44727Ti

   input number = 456,789,100,000.000e+00
  fraction digs = 0
specified radix = 10
     new number = 457G

   input number = +16777216
  fraction digs = ,
specified radix = 2
     new number = +16Mi

   input number = 1.2e101
  fraction digs = 
specified radix = 
     new number = 12googol

   input number = 446,835,273,728
  fraction digs = 1
specified radix = 
     new number = 446.8G

   input number = 1e36
  fraction digs = 
specified radix = 
     new number = 1U

   input number = 1e39
  fraction digs = 
specified radix = 
     new number = 1000U

Perl

Translation of: Perl 6

<lang perl>use List::Util qw(min max first);

sub sufficate {

   my($val, $type, $round) = @_;
   $type //= 'M';
  if ($type =~ /^\d$/) { $round = $type; $type = 'M' }
   my $s = ;
   if (substr($val,0,1) eq '-') { $s = '-'; $val = substr $val, 1 }
   $val =~ s/,//g;
   if ($val =~ m/e/i) {
       my ($m,$e) = split /[eE]/, $val;
       $val = ($e < 0) ? $m * 10**-$e : $m * 10**$e;
   }
   my %s;
   if ($type eq 'M') {
       my @x = qw<K M G T P E Z Y X W V U>;
       $s{$x[$_]} = 1000 * 10 ** ($_*3) for 0..$#x
   } elsif ($type eq 'B') {
       my @x = qw<Ki Mi Gi Ti Pi Ei Zi Yi Xi Wi Vi Ui>;
       $s{$x[$_]} = 2 ** (10*($_+1)) for 0..$#x
   } elsif ($type eq 'G') {
       $s{'google'} = 10**100
   } else {
       return 'What we have here is a failure to communicate...'
   }
   my $k;
   if (abs($val) < (my $m = min values %s)) {
       $k = first { $s{$_} == $m } keys %s;
   } elsif (abs($val) > (my $x = max values %s)) {
       $k = first { $s{$_} == $x } keys %s;
   } else {
       for my $key (sort { $s{$a} <=> $s{$b} } keys %s) {
           next unless abs($val)/$s{$key} < min values %s;
           $k = $key;
           last;
       }
   }
   my $final = abs($val)/$s{$k};
   $final = round($final,$round) if defined $round;
   $s . $final . $k

}

sub round {

   my($num,$dig) = @_;
   if    ($dig == 0) { int 0.5 + $num }
   elsif ($dig  < 0) { 10**-$dig * int(0.5 + $num/10**-$dig) }
   else              { my $fmt = '%.' . $dig . 'f'; sprintf $fmt, $num }

}

sub comma {

   my($i) = @_;
   my ($whole, $frac) = split /\./, $i;
   (my $s = reverse $whole) =~ s/(.{3})/$1,/g;
   ($s = reverse $s) =~ s/^,//;
   $frac = $frac.defined ? ".$frac" : ;
   return "$s$frac";

}

my @tests = (

  '87,654,321',
  '-998,877,665,544,332,211,000 3',
  '+112,233 0',
  '16,777,216 1',
  '456,789,100,000,000',
  '456,789,100,000,000 M 2',
  '456,789,100,000,000 B 5',
  '456,789,100,000.000e+00 M 0',
  '+16777216 B',
  '1.2e101 G',
  '347,344 M -2', # round to -2 past the decimal
  '1122334455 Q', # bad unit type example

);

printf "%33s : %s\n", $_, sufficate(split ' ', $_) for @tests;</lang>

Output:
                       87,654,321 : 87.654321M
   -998,877,665,544,332,211,000 3 : -998.878E
                       +112,233 0 : 112K
                     16,777,216 1 : 16.8M
              456,789,100,000,000 : 456.7891T
          456,789,100,000,000 M 2 : 456.79T
          456,789,100,000,000 B 5 : 415.44727Ti
      456,789,100,000.000e+00 M 0 : 457G
                      +16777216 B : 16Mi
                        1.2e101 G : 12google
                     347,344 M -2 : 300K
                     1122334455 Q : What we have here is a failure to communicate...

Perl 6

Works with: Rakudo version 2018.09

Pass in a number string, optionally a type, and optionally the number of digits to round to.

The types supported are B, M & G for binary, metric or gigantic. (At this point, the only gigantic unit is googol, so maybe it stands for googol. ¯\_(ツ)_/¯ )

If no type is specified, M (metric) is assumed.

If you desire the number to be rounded, pass in a number representing the placed past the decimal to round to. If you pass in a negative number for rounding, it will round to a negative number of places past the decimal.

<lang perl6>sub sufficate ($val is copy, $type is copy = 'M', $round is copy = Any) {

  if +$type ~~ Int { $round = $type; $type = 'M' }
  my $s = ;
  if $val.substr(0,1) eq '-' { $s = '-'; $val.=substr(1) }
  $val.=subst(',', , :g);
  if $val ~~ m:i/'e'/ {
      my ($m,$e) = $val.split(/<[eE]>/);
      $val = ($e < 0)
          ?? $m * FatRat.new(1,10**-$e)
          !! $m * 10**$e;
  }
  my %s = do given $type {
      when 'M' { <K M G T P E Z Y X W V U> Z=> (1000, * * 1000 … *) }
      when 'B' { <Ki Mi Gi Ti Pi Ei Zi Yi Xi Wi Vi Ui> Z=> (1024, * * 1024 … *) }
      when 'G' { google => 10**100 }
      default { return 'What we have here is a failure to communicate...' }
  }
  my $k = do given $val {
      when .abs < (my $m = min %s.values) { %s.first( *.value == $m ).key };
      when .abs > (my $x = max %s.values) { %s.first( *.value == $x ).key };
      default { %s.sort(*.value).first({$val.abs/%s{$_.key} < min %s.values}).key}
  }
  $round.defined
      ?? $s ~ comma(($val.abs/%s{$k}).round(10**-$round)) ~ $k
      !! $s ~ comma($val.abs/%s{$k}) ~ $k

}

sub comma ($i is copy) {

   my $s = $i < 0 ?? '-' !! ;
   my ($whole, $frac) = $i.split('.');
   $frac = $frac.defined ?? ".$frac" !! ;
   $s ~ $whole.abs.flip.comb(3).join(',').flip ~ $frac

}

    1. TESTING

my @tests =

  '87,654,321',
  '-998,877,665,544,332,211,000 3',
  '+112,233 0',
  '16,777,216 1',
  '456,789,100,000,000',
  '456,789,100,000,000 M 2',
  '456,789,100,000,000 B 5',
  '456,789,100,000.000e+00 M 0',
  '+16777216 B',
  '1.2e101 G',
  "{run('df', '/', :out).out.slurp.words[10] * 1024} B 2", # Linux df returns Kilobytes by default
  '347,344 M -2', # round to -2 past the decimal
  '1122334455 Q', # bad unit type example

printf "%33s : %s\n", $_, sufficate(|.words) for @tests;</lang>

Output:
                       87,654,321 : 87.654321M
   -998,877,665,544,332,211,000 3 : -998.878E
                       +112,233 0 : 112K
                     16,777,216 1 : 16.8M
              456,789,100,000,000 : 456.7891T
          456,789,100,000,000 M 2 : 456.79T
          456,789,100,000,000 B 5 : 415.44727Ti
      456,789,100,000.000e+00 M 0 : 457G
                      +16777216 B : 16Mi
                        1.2e101 G : 12google
                 703674818560 B 2 : 655.35Gi
                     347,344 M -2 : 300K
                     1122334455 Q : What we have here is a failure to communicate...

REXX

<lang rexx>/*REXX program to add a (either metric or "binary" metric) suffix to a decimal number.*/ @.= /*default value for the stemmed array. */ parse arg @.1 /*obtain optional arguments from the CL*/ if @.1== then do; @.1= ' 87,654,321 '

                      @.2=   '  -998,877,665,544,332,211,000    3        '
                      @.3=   '  +112,233                        0        '
                      @.4=   '   16,777,216                     1        '
                      @.5=   '   456,789,100,000,000            2        '
                      @.5=   '   456,789,100,000,000                     '
                      @.6=   '   456,789,100,000,000            2    10  '
                      @.7=   '   456,789,100,000,000            5     2  '
                      @.8=   '   456,789,100,000.000e+00        0    10  '
                      @.9=   '   +16777216                      ,     2  '
                      @.10=  '   1.2e101                                 '
                      @.11=  '   134,112,411,648                1        '    /*via DIR*/
                end                             /*@.11≡  amount of free space on my C: */
    do i=1  while @.i\==; say copies("─", 60) /*display a separator betweenst values.*/
    parse var  @.i  x  f  r  .                  /*get optional arguments from the list.*/
    say '     input number='          x         /*show original number     to the term.*/
    say '    fraction digs='             f      /*  "  specified fracDigs   "  "    "  */
    say '  specified radix='                r   /*  "  specified radix      "  "    "  */
    say '       new number='  suffize(x, f, r)  /*maybe append an "alphabetic" suffix. */
    end   /*i*/

exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ suffize: procedure; arg s 2 1 n, f, b /*obtain: sign, N, fractionDigs, base.*/

        if digits()<99  then numeric digits 500 /*use enough dec. digs for arithmetic. */
        @err = '***error*** (from SUFFIZE)  '   /*literal used when returning err msg. */
        if b==  then b= 10;              o= b /*assume a base  (ten)  if omitted.    */
        n= space( translate(n,,','), 0);   m= n /*elide commas from the  1st  argument.*/
        f= space( translate(f,,','), 0)         /*elide commas from the  2nd  argument.*/
        if \datatype(n, 'N')  then return @err "1st argument isn't numeric."
        if f==  then f= length(space(translate(n,,.), 0)) /*F omitted?  Use full len.*/
        if \datatype(f, 'W')  then return @err "2nd argument isn't an integer: "     f
        if f<0                then return @err "2nd argument can't be negative. "    f
        if \datatype(b, 'W')  then return @err "3rd argument isn't an integer. "     b
        if b\==10  &  b\==2   then return @err "3rd argument isn't a  10  or  2."    b
        if arg()>3            then return @err "too many arguments were specified."
        @=  ' KMGTPEZYXWVU'                     /*metric uppercase suffixes, with blank*/
        !.=;    !.2= 'i'                        /*set default suffix;  "binary" suffix.*/
        i= 3;   b= abs(b);  if b==2  then i= 10 /*a power of ten; or a power of  2**10 */
        if \datatype(n, 'N') | pos('E', n/1)\==0  then return m   /* ¬num or has an "E"*/
        sig=;    if s=='-' | s=="+"  then sig=s /*preserve the number's sign if present*/
        n= abs(n)                               /*possibly round number, & remove sign.*/
          do while n>=1e100 & b==10;  x=n/1e100 /*is N ≥ googol and base=10?  A googol?*/
          if pos(., x)\==0 & o<0  then leave    /*does # have a dec. point  or is B<0? */
          return sig  ||  x'googol'             /*maybe prepend the sign,  add GOOGOL. */
          end   /*while*/
          do j=length(@)-1  to 1  by -1  while n>0  /*see if #  is a multiple of 1024. */
          $= b ** (i*j)                             /*compute base raised to a power.  */
          if n<$  then iterate                      /*N not big enough?   Keep trying. */
          n= format(n/$, , min( digits(), f) ) / 1  /*reformat number with a fraction. */
          if pos(., n)\==0 & o<0  then return m     /*has a decimal point  or  is B<0? */
          leave                                     /*leave this DO loop at this point.*/
          end   /*j*/
        if n=0  then j=0                            /*N = 0?    Don't use any suffix.  */
        return sig||strip(n||substr(@, j+1,1))!.b   /*add sign, suffixes, strip blanks.*/</lang>
output   when using the internal default inputs:

(Shown at three-quarter size.)

────────────────────────────────────────────────────────────
     input number= 87,654,321
    fraction digs=
  specified radix=
       new number= 87.654321M
────────────────────────────────────────────────────────────
     input number= -998,877,665,544,332,211,000
    fraction digs= 3
  specified radix=
       new number= -998.878E
────────────────────────────────────────────────────────────
     input number= +112,233
    fraction digs= 0
  specified radix=
       new number= +112K
────────────────────────────────────────────────────────────
     input number= 16,777,216
    fraction digs= 1
  specified radix=
       new number= 16.8M
────────────────────────────────────────────────────────────
     input number= 456,789,100,000,000
    fraction digs=
  specified radix=
       new number= 456.7891T
────────────────────────────────────────────────────────────
     input number= 456,789,100,000,000
    fraction digs= 2
  specified radix= 10
       new number= 456.79T
────────────────────────────────────────────────────────────
     input number= 456,789,100,000,000
    fraction digs= 5
  specified radix= 2
       new number= 415.44727Ti
────────────────────────────────────────────────────────────
     input number= 456,789,100,000.000e+00
    fraction digs= 0
  specified radix= 10
       new number= 457G
────────────────────────────────────────────────────────────
     input number= +16777216
    fraction digs= ,
  specified radix= 2
       new number= +16Mi
────────────────────────────────────────────────────────────
     input number= 1.2e101
    fraction digs=
  specified radix=
       new number= 12googol
────────────────────────────────────────────────────────────
     input number= 134,112,411,648
    fraction digs= 1
  specified radix=
       new number= 134.1G

zkl

Uses GMP (GNU Multiple Precision Arithmetic Library for big ints. Error checking is nonexistent. <lang zkl>var [const] BI=Import.lib("zklBigNum"); // GMP var metric, binary, googol=BI("1e100"); metric,binary = metricBin();

  // suffix: 2 (binary), 10 (metric)
  // For this task, we'll assume BF numbers and treat everything as a big int

fcn sufficate(numStr, fracDigits=",", suffix="10"){

  var [const] numRE=RegExp(0'^\+*(([+-]*\.*\d+)[.]*(\d*)(e*[+-]*\d*))^);
  numRE.search((numStr - " ,").toLower());
  r:=numRE.matched[1];
  if(not r.find(".")) r=BI(r); // else ((((0,7),"1.2e101","1","2","e101")
  else  // convert float ("1.2" or "1.2e10") to big int
     r=BI(numRE.matched[2,*].concat())/(10).pow(numRE.matched[3].len());
  if(fracDigits==",") fracDigits=0; # "digits past decimal or none, if not specified"
  else                fracDigits=fracDigits.toInt();
  suffix=suffix.toInt();
  if(suffix.toInt()==2) nms,szs :=binary;
  else if(suffix==10)   nms,szs :=metric;
  else //throw(Exception.ValueError("Invalid suffix: %s".fmt(suffix)));
    return("Invalid suffix");
  ar:=r.abs();
  if(ar<szs[0]) return(r.toString());	// little bitty number
  i,sz,nm := szs.filter1n('>(ar)) - 1, szs[i], nms[i];  // False - 1 == True
  if(i==True)  // r > biggest unit
     if(r>=googol) sz,nm = googol, "googol";   // get out the big hammer
     else          sz,nm = szs[-1], nms[-1];   //    even if they want n^2
  fd,m := fracDigits + 4, BI(10).pow(fd);      // int --> float w/extra digits
  a,f,a := r*m/sz, (a%m).toFloat()/m, f + a/m; // to float for rounding
  fmt:="%%,.%df%%s".fmt(fracDigits).fmt;	// eg "%,.5f%s"
  return(fmt(a,nm));

}

  //-->Metric:(("K", "M",..), (1000,1000000,..))
  //   Bin:   (("Ki","Mi",..),(1024,1048576,..))

fcn metricBin{

  ss,m,b := "K M G T P E Z Y X W V U".split(), List(),List();
  ss.zipWith(m.append,[3..3*(ss.len()),3].apply(BI(10).pow)); // Metric
  ss.apply("append","i")
     .zipWith(b.append,[10..10*(ss.len()),10].apply(BI(2).pow)); // Binary
  return(m.filter22("".isType), b.filter22("".isType)); # split to ((strings),(nums))

}</lang> <lang zkl>testCases:=T(

  "87,654,321",
  "-998,877,665,544,332,211,000      3",
  "+112,233                          0",
  "16,777,216                        1",
  "456,789,100,000,000",
  "456,789,100,000,000               2      10",
  "456,789,100,000,000               5       2",
  "456,789,100,000.000e+00           0      10",
  "+16777216                         ,       2",
  "1.2e101",
  "446,835,273,728                   1",
  "1e36",
  "1e39", // there isn't a big enough suffix for this one but it's less than googol
  		# Linux df returns Kilobytes by default
  (1024*System.popen("df /","r").read().text.split()[10]).toString() + " 1 2 \"df /\"",
  "1122334455 , 666", # bad unit type example
  "10",  // don't suffix this

); foreach test in (testCases){

  test=test.split();
  "%33s : %s".fmt(test.concat(" "),sufficate(test.xplode())).println();

}</lang>

Output:
                       87,654,321 : 88M
   -998,877,665,544,332,211,000 3 : -997.878E
                       +112,233 0 : 112K
                     16,777,216 1 : 16.8M
              456,789,100,000,000 : 457T
         456,789,100,000,000 2 10 : 456.79T
          456,789,100,000,000 5 2 : 415.44727Ti
     456,789,100,000.000e+00 0 10 : 457G
                    +16777216 , 2 : 16Mi
                          1.2e101 : 12googol
                446,835,273,728 1 : 446.8G
                             1e36 : 1U
                             1e39 : 1,000U
           17221619712 1 2 "df /" : 16.0Gi
                 1122334455 , 666 : Invalid suffix
                               10 : 10