# _SHL

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The _SHL function is used to shift the bits of a numerical value to the left.

## Syntax

*result*= _SHL(*numericalVariable*,*numericalValue*)

## Parameters

*numericalVariable*is the variable to shift the bits of and can be of the following types: INTEGER, LONG,_INTEGER64, or _BYTE.- Integer values can be signed or _UNSIGNED.
*numericalValue*is the number of places to shift the bits.- While 0 is a valid value it will have no affect on the variable being shifted.

## Description

- Allows for multiplication of a value by 2 faster than normal multiplication (see example 2 below).
- Bits that reach the end of a variable's bit count are dropped (when using a variable of the same type - otherwise they will carry over).
- The type of variable used to store the results should match the type of the variable being shifted.

## Availability

**Version 1.3 and up**.

## Examples

*Example 1:*

A~%% = 1 'set right most bit of an_UNSIGNED _BYTE PRINT A~%% PRINT _SHL(A~%%,7) B~%% = _SHL(A~%%,8) 'shift the bit off the left 'edge' PRINT B~%%

1 128 0

*Example 2:*

A~%% = 1 FOR I%% = 0 TO 8 PRINT _SHL(A~%%, I%%) NEXT I%%

1 2 4 8 16 32 64 128 256

- Note: When directly PRINTing to screen, the result is calculated internally using a larger variable type so the left most bit is carried to the next value.
- To avoid this store the result in a variable of the same type before printing.

## See also

*Navigation:*