I know its a very basic question. But still, I am struggling to convert Binary to Integer and vice-versa in Simulink.
I could use a function block and use inbuilt Matlab functions to do it. But I, intend to use the Simulink blocks to convert Binary to decimal number.
Please suggest me how to do it or any pointers in the internet would be helpful.
You can use a Conversion block to convert back and forth between binary (i.e. boolean) types and various integer (int8, uint8, int16, etc.) or floating point (single or double) types.
I think this is what you're looking for:
How do I visualize the fixed-point data in binary or hex format using Simulink?
Related
How can I display the size of a 'real' (or 'float') in system verilog?
$bits can display size of int, shortint, longint, time, integer, etc. but cannot do the same for a real.
You cannot select individual bits of a real number, nor is there any other construct that requires to know the number of bits in a real number. So SystemVerilog does not need to provide a way to tell you.
real is not a real verilog type. It is intended for testbench or for analog calculations, not for design. Therefore it has no bit size associated with it.
However from lrm:
The real data type is the same as a C double. The shortreal data type is the same as a C float. The
realtime declarations shall be treated synonymously with real declarations and can be used
interchangeably. Variables of these three types are collectively referred to as real variables.
And there is a function which converts real to bits:
$realtobits converts values from a real type to a 64-bit vector representation of the real number.
and corresponding
$bitstoreal converts a bit pattern created by $realtobits to a value of the real type
So, you can assume that the size of real is 64 bits after conversion to bits.
I want to convert data(double precision,15 decimal points) to data of another type(quadruple precision,34 decimal points). So, I used vpa function like this:
data = sin(2*pi*frequency*time);
quad_data = vpa(data,34);
But, the type of the result is sym, not double. And when I checked each cell of the sym type data, 1x1 sym was created in each cell. I tried to use fft function using 'quad_data', but it didn't work. Is there any solution that I can change the decimal point of double type from 15 to 34?
The only numeric floating point types that MATLAB currently supports is double, single, and half. Extended precision types can be achieved via the Symbolix Toolbox (e.g., vpa) or 3rd party code (e.g., John D'Errico's FEX submission High Precision Floating HPF class). But even then, only a subset of floating point functions will typically be supported. If the function you are trying to use doesn't support the variable type, then you would have to supply your own function.
Also, you are not building vpa objects properly in the first place. Typically you would convert the operands to vpa first and then do arithmetic on them. Doing the arithmetic in double precision first as you are doing with data, and then converting to extended precision vpa, just adds garbage to the values. E.g., set the digits first and then use vpa('pi') to get the full extended precision version of pi as a vpa variable.
There is a commercial 3rd-party toolbox for this purpose, called the Multiprecision Computing Toolbox for MATLAB.
This tool implements many of the mathematical operations you would expect from double inputs, and according to benchmarks on the website, it's much faster than vpa.
Disclosure: I am not affiliated with the creators of this tool in any way, however I can say that we had a good experience with this tool for one of our lab's projects.
The other suggestion I can give is doing the high-precision arithmetic in an another language\environment to which MATLAB provides interfaces (e.g., C, python, java), and which should have the quad data type implemented.
I'm trying to send and receive data through a serial port using simulink (matlab 7.1) and d-space. The values I want to send and receive are doubles. Unfortunately for me the send and receive blocks use uint8 values. My question is how can I convert doubles into an array of uint8 values and vice versa? Are there simulink blocks for this or should I use embedded matlab functions?
Use the aptly named Data Type Conversion block, which does just that.
EDIT following discussion in the comments
Regarding scaling, here's a snapshot of something I did a long time ago. It's using CAN rather than serial, but the principle is the same. Here, it's slightly easier in that the signals are always positive, so I don't have to worry about scaling a negative number. 65535 is the max value for a uint16, and I would do the reverse scaling on the receiving end. When converting to uint16 (or uint8 as in your case, it automatically rounds the value, and you can specify that behaviour in the block mask).
There are pack and unpack blocks in simulink, search for them in simulink library browser. You could need som additional product, not sure which.
Does MATLAB support float16 operations? If so, how to convert a double matrix to float16? I am doing an arithmetic operation on a large matrix where 16-bit floating representation is sufficient for my representation. Representing by a double datatype takes 4 times more memory.
Is your matrix full? Otherwise, try sparse -- saves a lot of memory if there's lots of zero-valued elements.
AFAIK, float16 is not supported. Lowest you can go in float-datatype is with single, which is a 32-bit datatype:
A = single( rand(50) );
You could multiply by a constant and cast to int16, but you'd lose precision.
The numeric classes, which Matlab supports out of the box are the following:
int8
int16
int32
int64
uint8
uint16
uint32
uint64
single (32-bit float)
double (64-bit float)
plus the complex data type. So no 16-bit floats, unfortunately.
On Mathworks file exchange, there seems to be a half-precision float library. It requires MEX, however.
This might be an old question, but I found it in search for a similiar problem (half precision in matlab).
Things seemed to have changed in time:
https://www.mathworks.com/help/fixedpoint/ref/half.html
Half-precision seems to be supported nativeley by matlab now.
I'm relatively new to Simulink and I am looking for a possibility to extract 1-3 specific bits from one byte.
As far as I know the input format (bin, dec, hex) of the constant is irrelevant for the following!? But how can I say that the constant "1234" is hex and not dec?
In my model I use the "Constant Block" as my source (will be parametrised by a MATLAB variable which comes from a m-file).
A further processing with the "Extract Bits Block" causes an error on incompatible data types.
Can someone help me to deal with this issue?
Greets, poeschlorn
You should probably do the conversion hex->dec in your .m initialization file and use this value in Simulink.
Maybe this is not the most elegant solution, but I converted my input to decimal and then created a BCD representation of it via OR and AND logic blocks for further use.
If you have the Communications Toolbox/Blockset then you can use the Integer to Bit Converter block to do a conversion to a vector of binary digits then just extract the "bits" that you want. The Bit to Integer Converter block will do the reverse transformation.
If you don't have the Communicatins Blockset then it wouldn't be hard to do a similar thing to this using a plain MATLAB Function block.