usr/src/lib/libshell/common/scripts/primenumbers1.sh

   1 #!/usr/bin/ksh93
   2
   3 #
   4 # CDDL HEADER START
   5 #
   6 # The contents of this file are subject to the terms of the
   7 # Common Development and Distribution License (the "License").
   8 # You may not use this file except in compliance with the License.
   9 #
  10 # You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  11 # or http://www.opensolaris.org/os/licensing.
  12 # See the License for the specific language governing permissions
  13 # and limitations under the License.
  14 #
  15 # When distributing Covered Code, include this CDDL HEADER in each
  16 # file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  17 # If applicable, add the following below this CDDL HEADER, with the
  18 # fields enclosed by brackets "[]" replaced with your own identifying
  19 # information: Portions Copyright [yyyy] [name of copyright owner]
  20 #
  21 # CDDL HEADER END
  22 #
  23
  24 #
  25 # Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  26 #
  27
  28 #
  29 # primenumbers1 - a simple prime number generator
  30 #
  31
  32 # Solaris needs /usr/xpg6/bin:/usr/xpg4/bin because the tools in /usr/bin are not POSIX-conformant
  33 export PATH=/usr/xpg6/bin:/usr/xpg4/bin:/bin:/usr/bin
  34
  35 # Make sure all math stuff runs in the "C" locale to avoid problems
  36 # with alternative # radix point representations (e.g. ',' instead of
  37 # '.' in de_DE.*-locales). This needs to be set _before_ any
  38 # floating-point constants are defined in this script).
  39 if [[ "${LC_ALL}" != "" ]] ; then
  40     export \
  41         LC_MONETARY="${LC_ALL}" \
  42         LC_MESSAGES="${LC_ALL}" \
  43         LC_COLLATE="${LC_ALL}" \
  44         LC_CTYPE="${LC_ALL}"
  45         unset LC_ALL
  46 fi
  47 export LC_NUMERIC=C
  48
  49
  50 # check whether arg1 is a prime number via comparing it against the "pn" array
  51 function is_prime
  52 {
  53         integer i
  54         integer num=$1
  55         float   max_pn
  56
  57         (( max_pn=sqrt(num)+1. ))
  58
  59         for (( i=0 ; i < num_pn && pn[i] < max_pn ; i++)) ; do
  60                 (( num % pn[i] == 0 )) && return 1;
  61         done
  62         return 0
  63 }
  64
  65 # main
  66 set -o errexit
  67
  68 # get arguments
  69 integer max_prime=$1 # maximum prime number
  70 typeset outputformat=$2
  71
  72 # variables
  73 integer -a pn           # integer array for the prime numbers
  74 integer num_pn=1        # number of prime numbers
  75 integer n               # current number which should be tested
  76 pn[0]=2                 # start value
  77
  78 # prechecks
  79 (( max_prime > 1 )) || { print -u2 -f "%s: requires a positive integer as first input.\n" "$0" ; exit 1 ; }
  80
  81 # calculate prime numbers
  82 printf $"# %s: Calculating prime numbes from 1 to %i\n" "${ date '+%T' ; }" max_prime 1>&2
  83
  84 for (( n=3 ; n < max_prime ; n+=2 )) ; do
  85         if is_prime $n ; then
  86                 (( pn[num_pn++]=n ))
  87         fi
  88 done
  89
  90 # print results
  91 printf $"# %s: Calculation done, printing results:\n" "${ date '+%T' ; }" 1>&2
  92
  93 for (( n=0 ; n < num_pn ; n++ )) ; do
  94         # print prime number
  95         case ${outputformat} in
  96                 block)
  97                         printf $"%i$( (( n % 8 == 0 )) && print -r '\n' || print -r ',\t')" pn[n]
  98                         ;;
  99                 line)
 100                         printf $"%i\n" pn[n]
 101                         ;;
 102                 *)
 103                         printf $"prime %i:\t%i\n" n pn[n]
 104                         ;;
 105         esac
 106 done
 107
 108 if [[ ${outputformat} == "block" ]] && (( n % 8 != 1 )); then
 109         print
 110 fi
 111
 112 printf $"# %s: Done.\n" "${ date '+%T' ; }" 1>&2
 113
 114 #EOF.