# please help ???? how to convert hexadecimal ,octol to decimal values and back

felix thomas

Ranch Hand

Posts: 89

posted 14 years ago

For Decimal to Hex, just divide successively by 16, keeping the whole number result but noting the remainder of each division as you go, until you get a 0 result.

Take decimal 11948

11948 / 16 = 746 rem. 12

746 / 16 = 46 rem. 10

46 / 16 = 2 rem 14

2 / 16 = 0 rem 2

Then, go backwards through your list of remainders and convert each to hex. For this example, you will get 2EAC, which is the Hex representation of Decimal 11948

Same process when you convert Decimal to Octal, only your divisor will be 8.

For Hex to Decimal:

2EAC = (2 * 16^3) + (14 * 16^2) + (10 * 16^1) + (12 * 16^0) = 11948

When converting from Octal, use powers of 8.

[This message has been edited by JUNILU LACAR (edited June 21, 2001).]

Take decimal 11948

11948 / 16 = 746 rem. 12

746 / 16 = 46 rem. 10

46 / 16 = 2 rem 14

2 / 16 = 0 rem 2

Then, go backwards through your list of remainders and convert each to hex. For this example, you will get 2EAC, which is the Hex representation of Decimal 11948

Same process when you convert Decimal to Octal, only your divisor will be 8.

For Hex to Decimal:

2EAC = (2 * 16^3) + (14 * 16^2) + (10 * 16^1) + (12 * 16^0) = 11948

When converting from Octal, use powers of 8.

[This message has been edited by JUNILU LACAR (edited June 21, 2001).]

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Manfred Leonhardt

Ranch Hand

Posts: 1492

posted 14 years ago

Hi Felix,

Its easy, as long as you can perform a power function and some multiplication.

Hex to Dec:

Values 0 to 9 translate directly, A - F map to 10 to 15

Generic formula:

Decimal subValue = Hex digit * (16 ^ digit position)

where digit position starts at zero in the rightmost position and increments by one as you go left.

Once you get all the subtotals then you just add them together.

Examples:

0x4321

1*16^0 + 2*16^1 + 3*16^2 + 4*16^4

1*1 + 2*16 + 3*256 + 4*4096

1 + 32 + 768 + 16384

17185

0x7D

13*16^0 + 7*16^1

13*1 + 7*16

125

Oct to Dec:

Use the same formula but you use 8 instead of 16.

Values 0 - 7 translate directly

Decimal subValue = Oct digit * (8 ^ digit position)

Examples:

076

6 * 8^0 + 7 * 8^1

6*1 + 7*8

6 + 56

62

0432

2 * 8^0 + 3 * 8^1 + 4 * 8^2

2*1 + 3*8 + 4*64

2 + 24 + 256

282

Regards,

Manfred.

Its easy, as long as you can perform a power function and some multiplication.

Hex to Dec:

Values 0 to 9 translate directly, A - F map to 10 to 15

Generic formula:

Decimal subValue = Hex digit * (16 ^ digit position)

where digit position starts at zero in the rightmost position and increments by one as you go left.

Once you get all the subtotals then you just add them together.

Examples:

0x4321

1*16^0 + 2*16^1 + 3*16^2 + 4*16^4

1*1 + 2*16 + 3*256 + 4*4096

1 + 32 + 768 + 16384

17185

0x7D

13*16^0 + 7*16^1

13*1 + 7*16

125

Oct to Dec:

Use the same formula but you use 8 instead of 16.

Values 0 - 7 translate directly

Decimal subValue = Oct digit * (8 ^ digit position)

Examples:

076

6 * 8^0 + 7 * 8^1

6*1 + 7*8

6 + 56

62

0432

2 * 8^0 + 3 * 8^1 + 4 * 8^2

2*1 + 3*8 + 4*64

2 + 24 + 256

282

Regards,

Manfred.

Jane Griscti

Ranch Hand

Posts: 3141

posted 14 years ago

Hi Felix,

I have some notes on binary,octal,decimal, hexidecimal conversions posted at http://www.janeg.ca/scjp/oper/binhex.html

Hope they help.

------------------

Jane Griscti

Sun Certified Programmer for the Javaï¿½ 2 Platform

I have some notes on binary,octal,decimal, hexidecimal conversions posted at http://www.janeg.ca/scjp/oper/binhex.html

Hope they help.

------------------

Jane Griscti

Sun Certified Programmer for the Javaï¿½ 2 Platform

Jane Griscti

SCJP, Co-author Mike Meyers' Java 2 Certification Passport