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       jot - print sequential or random data


       jot [ options ] [ reps [ begin [ end [ s ] ] ] ]


       Jot  is  used to print out increasing, decreasing, random, or redundant
       data, usually numbers, one per line.  The  options  are  understood  as

       -r     Generate random data instead of sequential data, the default.

       -b word
              Just print word repetitively.

       -w word
              Print  word  with  the  generated  data  appended to it.  Octal,
              hexadecimal, exponential, ASCII, zero padded, and right-adjusted
              representations  are possible by using the appropriate printf(3)
              conversion specification inside word, in which case the data are
              inserted rather than appended.

       -c     This is an abbreviation for -w %c.

       -s string
              Print  data  separated  by  string.  Normally, newlines separate

       -n     Do not print the final newline normally appended to the  output.

       -p precision
              Print only as many digits or characters of the data as indicated
              by the integer precision.  In the absence of -p,  the  precision
              is  the  greater  of  the  precisions  of begin and end.  The -p
              option  is  overridden  by  whatever  appears  in  a   printf(3)
              conversion following -w.

       The last four arguments indicate, respectively, the number of data, the
       lower bound, the upper bound, and the step size or,  for  random  data,
       the  seed.   While  at  least one of them must appear, any of the other
       three may be omitted, and will be considered as such  if  given  as  -.
       Any  three  of  these  arguments  determines  the  fourth.  If four are
       specified and the given and computed values of reps conflict, the lower
       value  is  used.   If  fewer  than  three  are  specified, defaults are
       assigned left to right, except for s, which assumes its default  unless
       both begin and end are given.

       Defaults  for the four arguments are, respectively, 100, 1, 100, and 1,
       except that when random data  are  requested,  s  defaults  to  a  seed
       depending  upon  the  time  of day.  Reps is expected to be an unsigned
       integer, and if given as zero is taken to be infinite.  Begin  and  end
       may  be  given  as  real  numbers  or  as  characters  representing the
       corresponding value in ASCII.  The last argument must be a real number.

       Random numbers are obtained through random(3).  The name jot derives in
       part from iota, a function in APL.


       The command

              jot   21   -1   1.00

       prints 21 evenly spaced numbers increasing from -1  to  1.   The  ASCII
       character set is generated with

              jot   -c   128   0

       and the strings xaa through xaz with

              jot   -w   xa%c   26   a

       while 20 random 8-letter strings are produced with

              jot   -r   -c   160   a   z   |   rs   -g   0   8

       Infinitely many yes’s may be obtained through

              jot   -b   yes   0

       and thirty ed(1) substitution commands applying to lines 2, 7, 12, etc.
       is the result of

              jot   -w   %ds/old/new/   30   2   -   5

       The stuttering sequence 9, 9, 8, 8, 7, etc. can be produced by suitable
       choice of precision and step size, as in

              jot   0   9   -   -.5

       and a file containing exactly 1024 bytes is created with

              jot   -b   x   512   >   block

       Finally,  to  set  tabs  four  spaces apart starting from column 10 and
       ending in column 132, use

              expand   -`jot   -s,   -   10   132   4`

       and to print all lines 80 characters or longer,

              grep   `jot   -s   ""   -b   .   80`


       ed(1), expand(1), rs(1), yes(1), printf(3), random(3), expand(1)