# strtonum --- convert string to number## Arnold Robbins, arnold@skeeve.com, Public Domain# February, 2004function mystrtonum(str,        ret, chars, n, i, k, c){    if (str ~ /^0[0-7]*$/) {        # octal        n = length(str)        ret = 0        for (i = 1; i <= n; i++) {            c = substr(str, i, 1)            if ((k = index("01234567", c)) > 0)                k-- # adjust for 1-basing in awk            ret = ret * 8 + k        }    } else if (str ~ /^0[xX][0-9a-fA-f]+/) {        # hexadecimal        str = substr(str, 3)    # lop off leading 0x        n = length(str)        ret = 0        for (i = 1; i <= n; i++) {            c = substr(str, i, 1)            c = tolower(c)            if ((k = index("0123456789", c)) > 0)                k-- # adjust for 1-basing in awk            else if ((k = index("abcdef", c)) > 0)                k += 9            ret = ret * 16 + k        }    } else if (str ~ /^[-+]?([0-9]+([.][0-9]*([Ee][0-9]+)?)?|([.][0-9]+([Ee][-+]?[0-9]+)?))$/) {        # decimal number, possibly floating point        ret = str + 0    } else        ret = "NOT-A-NUMBER"    return ret}# BEGIN {     # gawk test harness#     a[1] = "25"#     a[2] = ".31"#     a[3] = "0123"#     a[4] = "0xdeadBEEF"#     a[5] = "123.45"#     a[6] = "1.e3"#     a[7] = "1.32"#     a[7] = "1.32E2"# #     for (i = 1; i in a; i++)#         print a[i], strtonum(a[i]), mystrtonum(a[i])# }