Count number of specific characters in input string - linux

Question

Im trying to count the number of letters, numbers and special characters in an input string
The user would type the string and then finish with a * to finish the program should then display a count for the number of letters numbers and special characters
So far i have this but i get errors on line 21 which i think is the else statement
The exact error message i get is "./masher3: line 21: 0: command not found"
#!/bin/bash
numcount=0
charcount=0
othercount=0
echo "Input string"
for char in $#
do
if [[ $char == "*" ]]
then
break
elif [[ $char == '0-9' ]]
then
$numcount = $numcount + 1
elif [[ $char == 'A-Z' ]]
then
$charcount = $charcount + 1
else
$othercount = $othercount + 1 <----- Error on this line
fi
done
echo $charcount

Answer 1

This program is written in pure bash (without calling any external programs).
Also look below the code – I added some more information.
#!/bin/bash
# Print the message without going to next line (-n)
echo -n "Your input string: "
# Read text from standard input. ‘-d '*'’ stops
# reading at first ‘*’ character. Remove it to
# terminate on press of key Enter.
# Result is stored in variable $input.
#
# -e enables backspace and other keys.
read -ed '*' input
# Jump to next line
echo
# Fill all counters with zeros
letters=0
digits=0
spaces=0
others=0
# While $input contains some text…
while [[ -n "$input" ]]
do
# Get the first character
char="${input:0:1}"
# Take everything from $input except
# the first character and store it again
# in $input
input="${input:1}"
# Is the character space?
if [[ "$char" == " " ]]
then
# Increase the $spaces variable by one
((spaces++))
# Else: If the $char after removal of all
# letters in (english) alphabet is empty string?
# That will be true when the $char is letter.
elif [[ -z "${char//[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ]/}" ]]
then
# Increase $letters
((letters++))
# Else: If the $char …
# Just the same for digits
elif [[ -z "${char//[0123456789]/}" ]]
then
((digits++))
# Else increase the $others variable
else
((others++))
fi
done
# Show values
echo "Letters: $letters"
echo "Digits: $digits"
echo "Spaces: $spaces"
echo "Other characters: $others"
Also open/download the Bash Reference Manual (available as single page, plaintext, PDF). You probably have one copy already installed if you use Linux. Try commands info bash (usually shows hypertext browser if installed) or man bash (single page documentation but usually the same). It is sometimes hard to understand for beginners but you will learn more information about this programming language.
Bash has many builtin commands (such as read, [[, echo, printf etc.) that work like ordinary commands. Their help is in the Reference Manual or can be shown by typing help command_name in your bash shell.

Answer 2

See my other answer for solution.
Your program is quite weird.
Assignment into variable looks like variable=42 (not $variable = 42)
You have to use $((…)) syntax to perform calculations
[[ $char == '0-9' ]] means “When the character is exactly 0-9
$char contains separate arguments of the program, not characters in input.
$othercount = … means “run command with name specified in variable $othercount with arguments = and ….
Assigning into variable in bash
You have to NOT write $ before variable name when you want to assign to it and you have to have NO whitespace before =:
my_variable=42
variable_2=$(($my_variable + 8))
echo $my_variable # Prints “50”