Print bit pattern of a number in Bash

bits.bash

# Pretty print binary pattern of a number
pb() {
    pn 2 4 "${1}"
}

# Pretty print octal value of a number
po() {
    pn 8 3 "${1}"
}

# Pretty print hexadecimal value of a number
ph() {
    pn 16 2 "${1}" | tr '[:upper:]' '[:lower:]'
}

# Pretty print denary value of a number
pd() {
    pn 10 3 "${1}" | sed -E 's/^0+//'
}

# Print encoded text in hexadecimal
pe() {
    echo 0x$(echo -n ${1} | xxd -p)
}

# Pretty print value of a number in given base and chomp
# $ pn base chomp number
# 0xxx xxxx xxxx
# ^   ^     ^  ^
# |   |     chomp size
# |   space
# prefix
pn() {
    local b=${1}  # base
    local c=${2}  # chomp size
    local n=0     # number
    local r=0     # remainder (prefix size)
    local u=${2}  # unit size

    # There are 8 bits in a byte
    if [[ "${b}" == 2 ]]; then
        u=8
    fi

    # Mathch decimal, octal (0123), hexadecimal (0xabcd) or base 2-64 number (2#10101010)
    if [[ "${3}" =~ ^(-)?([[:digit:]]+|0x[[:xdigit:]]+|[2-9][0-9]?#[0-9a-zA-Z@_]+)$ ]]; then
        # number
        n=$(printf '%X' $((${3})))     # To properly handle negative numbers
    elif [[ "${#3}" == 1 ]]; then
        # character
        n=$(printf '%X' "'${3}")
    else
        echo "Error: Can print only one number or character! (Received: ${3})"
        return 1
    fi

    n=$(bc <<< "obase=${b}; ibase=16; ${n}")
    r=$(( ${#n} % ${u} ))
    [[ ${r} == 0 ]] || r=$((${u} - ${r}))

    for i in $(seq ${r}); do
        n=$(sed 's/^/0/' <<< "${n}")
    done
    if [[ "${c}" > 0 ]]; then
        n=$(sed -E ":a s/([[:xdigit:]]+)([^ ]{${c}})/\1 \2/;ta" <<< "${n}")
    fi
    echo ${n}
}