MATLAB Answers

Yang
0

how to convert a 16-bit or 64-bit signed floting point to binary

Asked by Yang
on 28 Mar 2013

masters~ now I'm facing a problem that i have to convert some signed floating point numbers to binary, like -4.182068393394077e-04, or 1.3489.

do anybody have some idea or advices?

thanks

  5 Comments

Jan Simon
on 28 Mar 2013

It is not a question of you English, but it is currently not clear, what you mean by "16-bit floating point" type.

Yang
on 28 Mar 2013

i don't know what it called in english. what is the type of the number -4.4367e-04 called in english? floating poiont? signed?

Walter Roberson
on 28 Mar 2013

I have never encountered an unsigned floating point representation. I have encountered unsigned fixed point representations.

The closest you could get to -4.4367e-04 with a signed floating point representation would be to use a scheme with 1 sign bit, 5 exponent bits, 1 "hidden bit", and 10 bits of mantissa. That would allow you to express -(836/1024 + 1) / 2^12, or approximately -4.4346E-04. Notice this only gives you a few decimal places.

5 digits of accuracy requires 16 or 17 bits and the bits for the exponent. 1 sign bit, 5 bits of exponent, 1 hidden bit, 15 bits of mantissa = 21 bits of representation.

Products

No products are associated with this question.

2 Answers

Answer by Walter Roberson
on 28 Mar 2013
dec2bin(typecast(TheNumber, 'uint16'), 16) - '0'

  16 Comments

Yang
on 31 Mar 2013

I am hoping for a 1*N vector or N*1, both okey. if i could be, i will convinient for me to plug it in the frame which i use to input the channel encoder

Walter Roberson
on 31 Mar 2013

You need binary for the channel encoder. That is

dec2bin(typecast(TheNumber, 'uint16'), 16) - '0'

You can reshape() that to vector form. Just be sure to reshape() it back before using bin2dec() to convert the binary to numeric form.

Yang
on 1 Apr 2013

i would try this tonight, thanks


Answer by Jan Simon
on 28 Mar 2013

What exactly is a "binary stream"? It could be a vector of doubles, which contains only ones and zeros. Of a vector of type LOGICAL, or UINT8. Or remember, that all numbers are stored in binary format on a computer, so perhaps this is enough already:

x = pi;
x_bin = typecast(x, 'uint8')

  2 Comments

Yang
on 28 Mar 2013

thank you so much. the friend upside gave me a code so i convert a vector of floating point to a vector which only ones and zeros. what could i do to convert it back~

Yang
on 28 Mar 2013

couas i want to convert a celp parameter vector into binary stream so that i could input it to a Turbo encoder to do some tests for my graduation design. is that clear about "binary stream"?


Discover MakerZone

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi test

Learn more

Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply Today

MATLAB Academy

New to MATLAB?

Learn MATLAB today!