hbars - create horizontal bar in Bash script

The hbar script can be used to create text based or web page horizontal bars.

Installation and Usage

To install and use the Bash script:

wget https://raw.githubusercontent.com/metcalfepete/hbars/main/hbars
chmod +x hbars
# to make it available 
sudo mv hbars /usr/bin

The script accepts both piped and command data

$ hbars
usage: hbars [option] [data]
  -h --help     print this usage and exit
  -c --color    set color to all bars (default 7=white)
                 (0-grey,1-red,2=green,3=yellow,4=blue,5=magenta,6=cyan,7=white)
  -p --pretty   add different colors to bars (-c overrides)
  -t --title    top title
  -w --width    max width of bar (default 50)
  -W --Web      make output HTML formatted
  -f --fontsize fontsize for web output (default 24)

 examples:
   echo 'temp,33,C;pressure,14,psi' | ./hbars -t Weather -p -w 40 
   ./hbars -t Weather -p -w 40  'temp,33;pressure,14' 
   cat data.txt | ./hbars -W -f 24 -t 'Raspi Data' > data.htm

Options Arguments:

-c -- color, the color can be set for all bars. The color is based on the ANSI color settings: 0-grey,1-red,2=green,3=yellow,4=blue,5=magenta,6=cyan,7=white (default 7=white) -p -- pretty, each bar is given a unique color in the order of 1,2,3... -t -- title. A string. For web page HTML tags can be include: Web example: -t "

Some Bars" -w --width, width of bar. Max value is scaled to this width value (default 50) -W --Web, output is HTML formatted. Output show be directed to a file -f --fontsize, fontsize for web output (default 24)

Examples:

The data structure is: label, value, (units - optional), (color -optional); Each item is separated withhu ',' and each item group is terminated with ";".

An example with data on the command line:

$ $  hbars -t Weather  -w 40 -t "Weather Data" "temp,33;humidity,80"

            Weather Data

       temp ████████████████ 33 

   humidity ████████████████████████████████████████ 80

At example of data piped in:

$ echo 'temp,33,C;pressure,14,psi' | hbars -t Weather  -w 40 

            Weather

       temp ████████████████████████████████████████ 33 C

   pressure ████████████████ 14 psi

Background

To create a static bar an printf statements can be used. The seq {0..10} can be used to repeat an ASCII '█' fill character 10 times.

$ printf 'LABEL: ' ; \
  printf '█%.0s' {1..10} ; \
  printf ' 10\n'

LABEL: ████████████████████ 10

Unfortunately the printf statement has some limitations on variable substitution. A simple workaround is to create a string and then eval it:

$ label="temp"; val=20;
$ bar="printf '█%.0s' {1..$val}" ; 
$ printf '\n%-5s ' $label; eval $bar ; printf ' %d\n' $val

temp  ████████████████████ 20

Colored Bar

The tput setaf command can change the foreground, and tput setab is used for background colours. Colour codes are:

tput setab [1-7] # Set the background colour using ANSI escape
tput setaf [1-7] # Set the foreground colour using ANSI escape

Num  Colour    #define         R G B

0    black     COLOR_BLACK     0,0,0
1    red       COLOR_RED       1,0,0
2    green     COLOR_GREEN     0,1,0
3    yellow    COLOR_YELLOW    1,1,0
4    blue      COLOR_BLUE      0,0,1
5    magenta   COLOR_MAGENTA   1,0,1
6    cyan      COLOR_CYAN      0,1,1
7    white     COLOR_WHITE     1,1,1

To reset colours back to the defaults use: tput sgr0