Re: Bit Operation - BITAND

Here is some procedures that I wrote that do testing and masking. The forum
is going to screw up the code so let me know if you want sent direct.

* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* AttributeOn
* This function checks to determine if bit flag is set for requested
* attribute.
* Input - Attribute
* - Attribute flags
* Output - None
* Returns - True or False
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
p AttributeOn...
p b
d pi Like(StdLgl)
d InAttribute...
d Like(StdIntSml)
d Value
d InAttributeFlags...
d Like(StdIntSml)
d Value
/Free

// Color bits are masked out(High order).
If %BitAnd(MaskHighOrderBits(InAttributeFlags):
InAttribute ) = x'00';
Return cFalse;
Else;
Return cTrue;
EndIf;

/End-Free
p e
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* ColorOn
* This function checks to determine if a color is on.
* attribute.
* Input - Color value
* - Attribute flags
* Output - None
* Returns - True or False
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
p ColorOn...
p b
d pi Like(StdLgl)
d InColorValue...
d Like(StdIntSml)
d Value
d InAttributeFlags...
d Like(StdIntSml)
d Value
/Free

// Attribute bits are masked out(Low order).
If %BitAnd(MaskLowOrderBits(InAttributeFlags):
InColorValue ) = x'00';
Return cFalse;
Else;
Return cTrue;
EndIf;

/End-Free
p e
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* NoAttributes
* This function checks to determine if there are no attributes
* passed. (No low order bits).
* Input - Attribute flags
* Output - None
* Returns - True or False
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
p NoAttributes...
p b
d pi Like(StdLgl)
d InAttributeFlags...
d Like(StdIntSml)
d Value
/Free

// Color bits are masked out(High order).
If MaskHighOrderBits(InAttributeFlags) = 0;
Return cTrue;
Else;
Return cFalse;
EndIf;

/End-Free
p e
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* MaskHighOrderBits
* This function removes high order bits from a small integer
* field.
* Input - Field to mask.
* Output - None
* Returns - Masked field.
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
p MaskHighOrderBits...
p b
d pi Like(StdIntSml)
d InFieldToMask...
d Like(StdIntSml)
d Value

d cMaskHighOrderBits...
d c 255
/Free

Return %BitAnd(InFieldToMask :
cMaskHighOrderBits);

/End-Free
p e
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
* MaskLowOrderbits
* This function removes low order bits from a small integer
* field.
* Input - Field to mask.
* Output - None
* Returns - Masked field.
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
p MaskLowOrderBits...
p b
d pi Like(StdIntSml)
d InFieldToMask...
d Like(StdIntSml)
d Value

d cMaskLowOrderBits...
d c 65280
/Free

Return %BitAnd(InFieldtoMask :
cMaskLowOrderBits);

/End-Free
p e

On Mon, Jun 22, 2009 at 10:24 AM, Adam Glauser <adamglauser@xxxxxxxxx>wrote:

Michael Ryan wrote:

Hi Adam -

Actually, I have to test each bit in PrimaryBitMap to see if that bit is

on

or off.

It's too bad that there isn't a %testbit() function. As far as I know,
the most straightforward way of doing this would be to define a "mask"
for each bit you want to test.

For example, say your bit map is a set of customer information flags.
http://code.midrange.com/71a457c8f6.html

Another possibility would be to define eight masks, one mask for each
bit in a byte, then loop through each byte in the bitmap field, setting
elements of a 64-element array of indicators to *ON or *OFF as
appropriate. Then you could set up constants to name each of the bits

D ACTIVE_CUST...
D C 1
// binary 01000000....0000, test second bit
D PAYMENT_DUE_MASK...
D C 2

and say things like

if (flag(ACTIVE_CUST) = *ON);
// do active cust processing

Yet another possibility is to build a service program with one procedure
per flag, where each procedure would use one of the masks from the first
example. This might be the best way to go if you need to test these
flags in more than one place.

HTH,
Adam
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