MATLAB and C language comparison example: random number generation

MATLAB and C language comparison example: random number generation

Author: Kailugaji - Blog Park http://www.cnblogs.com/kailugaji/

1. Integer random number generator function

1. C language program

int intrand(int lower,int upper)
{
    double X = (double)rand() / RAND_MAX;
    return lower+(int)(X*(upper-lower));
}

2. MATLAB program

intrand.m

function y= intrand(lower,upper)
 % generate random numbers 
x =rand( 1 , 1 );      
z=int32(x*(upper-lower));
y=lower+z;
end

The result of running the matlab program:

>> y=intrand(0,10)

y =

           8

2. Double-precision random number generation

1. C language program

double doublerand(double lower,double upper)
{
    double x = (double)rand() / RAND_MAX;
    return lower+x*(upper-lower);
}

2. MATLAB program

doublerand.m

function y= doublerand(lower,upper)
 % Generate random number 
x =rand( 1 , 1 );        
y=lower+x.*(upper-lower);
end

The result of running the matlab program:

>> y=doublerand(0,10)

y =

    6.3236

Among them, the RAND_MAX of the C language is a character constant defined by the macro in stdlib.h:

#define RAND_MAX 0x7FFF

The minimum value is 32767 and the maximum value is 2147483647

Usually RAND_MAX can be used when generating random decimals.

If there are deficiencies in the function, please give me more advice.