basma wrote:
> i search but didn't find any thing helpe me.
What did you search for?

> any idea plz....
This is exaclty what you need (according to your requirements):

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.math_real.ALL;

entity findmax is
  port (
    clk : in std_logic;
    clr : in std_logic;
    din : in real;
    max : out real;
  );
end findmax ;

architecture Behavioral of findmax is
signal m : real := 0.0;
begin
  process begin
    wait until rising_edge(clk);
      if clr='1' then
        m <= 0.0;
      elsif din>m then
        m <= din;
      end if;    
    end if;
  end process;
  
  max <= m;
end Behavioral;

Of course I already added a clock and a clear signal. Otherwise (without 
clock and clear) it would look much less complicated:

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.math_real.ALL;

entity findmax is
  port (
    din : in real;
    max : out real;
  );
end findmax ;

architecture Behavioral of findmax is
signal m : real := 0.0;
begin
  m <= din when m<din else m;
  max <= m;
end Behavioral;

jeff wrote:
> No semicolon after max: out real
Indeed, but I think that little syntax flaw will not be the biggest 
problem here...

thanks a lot lkmiller ,but i want to know how can i gave the floating 
numbers to xilinx simulation program

Basma Hassan wrote:
> but i want to know how can i gave the floating numbers to xilinx
> simulation program
And where do the numbers come from?
Where are the numbers generated and/or stored?

Lothar Miller wrote:
> Basma Hassan wrote:
>> but i want to know how can i gave the floating numbers to xilinx
>> simulation program
> And where do the numbers come from?
> Where are the numbers generated and/or stored?

i mean to test the code i should gave numbers from test bench waveform 
instead of write test bench .

Basma Hassan wrote:
> i mean to test the code i should gave numbers from test bench waveform
> instead of write test bench .
I do not understand the problem...  :-/
Please write at least 5 sentences that describe your task (including 
answers to my previous questions).

if i want to find the max value in 
(0.3251,0.2536,0.2147,0.3669.............)
how to test it and find the max value

Basma Hassan wrote:
> if i want to find the max value in
> (0.3251,0.2536,0.2147,0.3669.............)
Do you remember my unanswered questions?
Lothar Miller wrote:
> And where do the numbers come from?
> Where are the numbers generated and/or stored?

Basma Hassan wrote:
> how to test it and find the max value
Show the definition of your data at least. Is it an array of floating 
point numbers? How is this array defined?