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71 lines
1.4 KiB
Markdown
71 lines
1.4 KiB
Markdown
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The [_SHR](_SHR) function is used to shift the bits of a numerical value to the right.
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## Syntax
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> result = [_SHR](_SHR)(numericalVariable, numericalValue)
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## Parameter(s)
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* numericalVariable is the variable to shift the bits of and can be of the following types: [INTEGER](INTEGER), [LONG](LONG), [_INTEGER64](_INTEGER64), or [_BYTE](_BYTE).
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* Integer values can be signed or [_UNSIGNED](_UNSIGNED).
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* numericalValue the number of places to shift the bits.
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* While 0 is a valid value it will have no affect on the variable being shifted.
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## Description
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* Allows for division of a value by 2 faster than normal division (see example 2 below).
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* Bits that reach the end of a variables bit count are dropped.
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* The type of variable used to store the results should match the type of the variable being shifted.
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* NOTE: When dealing with SIGNED variables, shifting the bits right will leave the sign bit set. This is due to how C++ deals with bit shifting under the hood.
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## Availability
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* Version 1.3 and up.
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## Example(s)
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```vb
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A~%% = 128 'set left most bit of an_UNSIGNED _BYTE
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PRINT A~%%
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PRINT _SHR(A~%%,7)
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PRINT _SHR(A~%%,8) 'shift the bit off the right 'edge'
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```
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```text
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128
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1
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0
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```
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```vb
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A~%% = 128
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FOR I%% = 0 TO 8
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PRINT _SHR(A~%%, I%%)
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NEXT I%%
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```
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```text
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128
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64
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32
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16
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8
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4
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2
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1
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0
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```
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## See Also
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* [_SHL](_SHL), [INTEGER](INTEGER), [LONG](LONG)
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* [_BYTE](_BYTE), [_INTEGER64](_INTEGER64)
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