# NumPy - left_shift() function

The Bitwise left shift operator (<<) takes the two numbers and left shift the bits of first operand by number of place specified by second operand. For example: for left shifting the bits of x by y places, the expression (x<<y) can be used. It is equivalent to multiplying x by 2y.

The example below describes how left shift operator works:

```1000 << 2 returns 4000

(In Binary)
1000         ->    1111101000
<< 2                     |  left shift the bits
-----                    V  by 2 places
4000         <-  111110100000
(In Binary)
```

The NumPy left_shift() function shifts the bits of an integer to the left. Bits are shifted to the left by appending y 0s at the right of x. This operation is equivalent to multiplying x by 2y. This ufunc implements the C/Python operator <<.

### Syntax

```numpy.left_shift(x, y, out=None)
```

### Parameters

 `x` `Required. `Specify the input array. `y` `Required. `Specify the number of zeros to append to x. Has to be non-negative. If x.shape != y.shape, they must be broadcastable to a common shape. `out` `Optional. `Specify a location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned.

### Return Value

Returns x with bits shifted y times to the left. This is a scalar if both x and y are scalars.

### Example:

In the example below, the left_shift() function is used to compute the left shift operation using two scalars.

```import numpy as np

x = 1000
y = 2

#left shift operation
z = np.left_shift(x, y)

#Displaying the result
print("z =", z)
```

The output of the above code will be:

```z = 4000
```

### Example:

The left_shift() function can be used with arrays where it computes the left shift operation of the array element-wise.

```import numpy as np

x = np.array([[10, 20],[30, 40]])
y = np.array([[0, 1],[2, 3]])

#left shift operation
z = np.left_shift(x, y)

#Displaying the result
print("z =")
print(z)
```

The output of the above code will be:

```z =
[[ 10  40]
[120 320]]
```

❮ NumPy - Binary Operators

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