Campbell CR850, Руководство оператора

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Section 7. Installation
144
CRBasic Example 20. Conversion of FLOAT / LONG to Boolean
Public Fa As Float
Public Fb As Float
Public L As Long
Public Ba As Boolean
Public Bb As Boolean
Public Bc As Boolean
BeginProg
Fa = 0
Fb = 0.125
L = 126
Ba = Fa
'This will set Ba = False (0)
Bb = Fb 'This will Set Bb = True (-1)
Bc = L 'This will Set Bc = True (-1)
EndProg
FLOAT from LONG or Boolean
When a LONG or Boolean is converted to FLOAT , the integer value is loaded
into the FLOAT . Boolean s are converted to -1 or 0 . LONG integers greater than
24 bits (16,777,215; the size of the mantissa for a FLOAT ) will lose resolution
when converted to FLOAT .
LONG from FLOAT or Boolean
When converted to Long, Boolean is converted to -1 or 0 . When a FLOAT is
converted to a LONG , it is truncated. This conversion is the same as the INT
function ( Arithmetic Functions
(p. 475)
). The conversion is to an integer equal to or
less than the value of the float (e.g., 4.6 becomes 4, -4.6 becomes -5).
If a FLOAT is greater than the largest allowable LONG (+2,147,483,647), the
integer is set to the maximum. If a FLOAT is less than the smallest allowable
LONG (-2,147,483,648), the integer is set to the minimum.
Integers in Expressions
LONG s are evaluated in expressions as integers when possible. CRBasic example
Evaluation of Integers
(p. 144)
illustrates evaluation of integers as LONG s and
FLOAT s.
CRBasic Example 21. Evaluation of Integers
Public X, I As Long
BeginProg
I = 126
X = (I+3) * 3.4
'I+3 is evaluated as an integer, then converted to FLOAT before
'it is multiplied by 3.4
EndProg