I think the question has been answered, but I'll post a couple of other formulations for you. Sometimes seeing other programming techniques is helpful.

This is from a CRC program that was coded in assembly, C and Perl. The relevant part prints the 16 bit CRC values.

The Perl code:
A lab requirement was to print the 16 bits like: 0101 1011 1100 0001 

printf "The CRC Bytes (binary)  : %04b %04b %04b %04b\n", 
                        $CRC_byte1>>4, $CRC_byte1 & 0xF, 
                        $CRC_byte2>>4, $CRC_byte2 & 0xF;

[download]
In Perl, there is a %b "format spec" for printf - described on the sprintf man page. I didn't mess with a loop, and rather just used some simple binary shift and "and" operations to extract each group of 4 bits (a hex digit actually) from the 2 bytes comprising the 16 bit CRC value. In a case like this, with fixed format (always 16 binary digits), no loop is needed. Oh, I should point out that it is known that $CRC_byte1 and $CRC_byte2 only use 8 bits each.

The C code:
There is no %b format spec in standard C. So I did it a bit differently... 

void dump_16bits(unsigned int any_16bits)
{
    int i;
    for (i=0; i<16; i++)
    {
        if (i%4==0 )printf (" "); 
        printf ("%c", (any_16bits & 0x8000) ? '1':'0');
        any_16bits <<=1;  #a keft shift 1 bit
    }
}

[download]
This uses the modulo operator (%) to put a space in every 4 binary digits. The printf statement here prints '1' or '0' depending upon the most significant bit (specifically the 2**15 bit)

The modulo operator (%) and the ternary operator (any_16bits & 0x8000) ? '1':'0' both exist in Perl also and you may on occasion find a use for them. In this case, the Perl version if this was "translated as directly from C to Perl" as possible, would be almost identical.

This was a demo for my lab students and I used different techniques on purpose. I'll spare you the assembly code!

My purpose was just to demo some other techniques for you.

In reply to Re: decimal to binary by Marshall
in thread decimal to binary by divyaimca

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.