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Re: Meaning of the expression [message #93641 is a reply to message #93640]

Tue, 20 September 2016 02:39

Markus Schmassmann
Messages: 129
Registered: April 2016

Senior Member

On 09/20/2016 10:05 AM, Helder wrote:
> On Tuesday, September 20, 2016 at 8:05:22 AM UTC+2, Sanu wrote:
>> exp = 'BYTE(B1 NE 0)*1'
>>
>> What is the meaning of this expression???
> It's not an expression, it's an assignment.
> It assigns a string to the variable exp.
> However, the math displayed in the string is somewhat strange:
> - b1 NE 0 will always give a byte result, so there is no need for the byte function
> - the *1 will convert the result to an integer or long (depending on the compiler options)
- B1 NE 0 is of type BYTE with the Boolean flag set, the BYTE() function
removes that flag
- the only difference the Boolean flag makes, is to HELP,
ISA(XXX,/boolean) and implied print
- once *1 is applied, this does not matter

if compile_opt idl2 or defint32 is set, the math in the string could be
shortened to 'LONG(B1 NE 0)', otherwise 'FIX(B1 NE 0)'

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[Message index]

		Meaning of the expression By: Suresh Negi on Mon, 19 September 2016 23:05
		Re: Meaning of the expression By: Helder Marchetto on Tue, 20 September 2016 01:05
		Re: Meaning of the expression By: Markus Schmassmann on Tue, 20 September 2016 02:39
		Re: Meaning of the expression By: Helder Marchetto on Tue, 20 September 2016 02:54
		Re: Meaning of the expression By: Markus Schmassmann on Tue, 20 September 2016 06:55
		Re: Meaning of the expression By: Suresh Negi on Tue, 20 September 2016 23:10

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