Positron Compiler Documentation

dFloor

Positron16 · Revision 1.1.3.5 · PDF page 109

Assignment Variable = dFloor(pVariable)

Deduce the floor of a 64-bit floating point value. Returns the largest whole value less than or equal to Variable.

pVariable can be a floating point constant, variable or expression. Assignment Variable can be any valid variable type.

Device = 24FJ64GA002           ' Select the device to compile for
Declare Xtal = 16      ' Tell the compiler the device will be operating at 16MHz

Declare Hserial_Baud = 9600    ' USART1 Baud rate
Declare Hrsout1_Pin = PORTB.14 ' Select the pin for TX with USART1

Dim DoubleIn as Double        ' Holds the value to Asin
Dim DoubleOut as Double        ' Holds the result of the Asin

PPS_Output(cOut_Pin_RP14, cOut_Fn_U1TX)  ' Make Pin RB14 U1TX

DoubleIn = 3.8                  ' Load the variable
DoubleOut = dFloor(DoubleIn)   ' Extract the floor value
HrsoutLn Dec DoubleOut        ' Display the result (3.0)

The compiler uses the stack as temporary storage when performing 64-bit floating point library routines, therefore, it may be required to increase the stack size from the default 120 words to 200 words using the Stack_Size declare. If the program resets with a stack underflow/overflow exception when running, the stack size is insufficient and requires increasing.

When implementing trigonometry, or other built in, functions within an expression, always wrap them in parenthesis, otherwise the parser may consider the extra operands as part of the trigonometry parameter and produce an incorrect result. For example:

MyAssignment = (dFloor(MyVar1)) + MyVar2
View original PDF page 109Open page in PDFOriginal PDF page 109