# Difference between revisions of "Generate a random number"

## Implementations

### bash

print a random integer

```val="\$RANDOM"
echo \$RANDOM
```

### C

```#include <stdlib.h>
#include <time.h>

srand(time(NULL)); /* initialize random seed */
rand();            /* Generate a random int from 0 to RAND_MAX */
rand() % 100;      /* Generate a random int from 0 to 99 */
rand() % 100 + 1;  /* Generate a random int from 1 to 100 */
rand() % 30 + 100; /* Generate a random int from 100 to 129 */
```

### Erlang

```% Generate a random real number between 0.0 and 1.0
F = random:uniform().

% Generate a random integer between 1 and 100
I = random:uniform(100).
```

### Java

Generate a random int from 0 to n

``` java.util.Random rand = new java.util.Random();
i = rand.nextInt(n+1);
```

### OCaml

```# Random.int 15;;
- : int = 9
```

### Perl

```rand; # Generate a random real number between 0 and 1
rand(100); # Generate a random real number between 0 and 100
int(rand(100)); # Generate a random integer between 0 and 99
```

### PHP

```  \$int = rand(99);
//\$int is a random number between 0 and 99 inclusive
```

### Python

```import random

# Generate a random integer between 0 and n, exclusive
random.randrange(n)

# Generate a random integer between m and n, inclusive
random.randrange(m, n + 1)
```

### Ruby

```# Generate a random real number between 0 and 1
x = rand      # 0.0 <= x < 1.0

# Generate a random integer between 0 and n, exclusive
i = rand(n) 　 # 0 <= i < n
```

### Seed7

Generate a random integer between m and n inclusive

``` rand(m, n)
```

### Tcl

```# Random integer between 0..10
set n [expr {int(10*rand())}]
```

### Zsh

```# Generate pseudo-random number between 0 and 32767.
\$RANDOM

# Generate pseudo-random number between 0 and 9.
\$RANDOM % 10

# Or

typeset -F SECONDS
typeset -F6 SECONDS
\${SECONDS#*.} % 10

# Generate pseudo-random number between 0 and 1 using module of mathematical functions.
rand48()

# Or using Cliff random number generator
# http://mathworld.wolfram.com/CliffRandomNumberGenerator.html

function cliff_rand {