how to create random double in specific range?

HI, randi function Can only generate integers in specific range.

    num = randi([1,3],[1,10],'double');

how to create double numbers in range such as [0.2,1.2]?

Answer 1

[Cyrus]

For generating double numbers you can use:

r = rand( 1, 3 ,'double')

r = 1×3

0.8499 0.2298 0.4419

and to have them in a specific range you can use the following source: https://www.mathworks.com/help/matlab/math/floating-point-numbers-within-specific-range.html

which is:

a = 50;
b = 100;
r = (b-a).*rand(1000,1) + a;

thus, finally:

numElements = 10;
a = 0.2;
b = 1.2;
r= (b-a).*rand(1, numElements, 'double') + a; % [SL: added the missing "+a" term]

The result:

r

r = 1×10

0.3118 1.1751 0.8208 0.8696 0.6526 1.1281 0.4074 0.5364 0.2122 0.9621

Answer 2

[Carolina Escobar]

e = rand(0.1,1)

[Steven Lord]

This will throw an error.

e = rand(0.1, 1)

Error using rand
Size inputs must be integers.

As the error message indicates, the size inputs to rand must contain integer values.