Campbell Scientific CR6 CR6 Measurement and Control System - Page 164

Logical Expressions

Page 164 highlights

Section 7. Installation CRBasic Example 17. Evaluation of Integers ' the evaluation of integers. Public I As Long Public X As Float BeginProg I = 126 X = (I+3) * 3.4 'I+3 is evaluated as an integer, then converted to Float data type before it is 'multiplied by 3.4. EndProg Constants Conversion Constants are not declared with a data type, so the CR6 assigns the data type as needed. If a constant (either entered as a number or declared with CONST) can be expressed correctly as an integer, the compiler will use the type that is most efficient in each expression. The integer version is used if possible, for example, if the expression has not yet encountered a FLOAT. CRBasic example Constants to LONGs or FLOATs (p. 164) lists a programming case wherein a value normally considered an integer (10) is assigned by the CR6 to be As FLOAT. CRBasic Example 18. Constants to LONGs or FLOATs ' conversion of constants to Long or Float data types. Public L As Long Public F1 As Float Public F2 As Float Const ID = 10 BeginProg F1 = F2 + ID L = ID * 5 EndProg In CRBasic example Constants to LONGs or FLOATs (p. 164), I is an integer. A1 and A2 are FLOATS. The number 5 is loaded As FLOAT to add efficiently with constant ID, which was compiled As FLOAT for the previous expression to avoid an inefficient runtime conversion from LONG to FLOAT before each floating point addition. 7.8.3.10.4 Logical Expressions Measurements can indicate absence or presence of an event. For example, an RH measurement of 100% indicates a condensation event such as fog, rain, or dew. The CR6 can render the state of the event into binary form for further processing, so i.e the event is either occurring (true), or the event has not occurred (false). True = -1, False = 0 In all cases, the argument 0 is translated as FALSE in logical expressions; by extension, any non-zero number is considered "non-FALSE." However, the 164

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Section 7.
Installation
CRBasic Example 17.
Evaluation of Integers
'<TPED> the evaluation of integers.
Public
I
As Long
Public
X
As Float
BeginProg
I = 126
X = (I+3) * 3.4
'I+3 is evaluated as an integer, then converted to Float data type before it is
'multiplied by 3.4.
EndProg
Constants Conversion
Constants are not declared with a data type, so the CR6 assigns the data type as
needed. If a constant (either entered as a number or declared with
CONST
) can be
expressed correctly as an integer, the compiler will use the type that is most
efficient in each expression. The integer version is used if possible, for example, if
the expression has not yet encountered a
FLOAT
. CRBasic example
Constants to
LONGs or FLOATs
(p. 164)
lists a programming case wherein a value normally
considered an integer (10) is assigned by the CR6 to be
As FLOAT
.
CRBasic Example 18.
Constants to LONGs or FLOATs
'<TPED> conversion of constants to Long or Float data types.
Public
L
As Long
Public
F1
As Float
Public
F2
As Float
Const
ID = 10
BeginProg
F1 = F2 + ID
L = ID * 5
EndProg
In CRBasic example
Constants to LONGs or FLOATs
(p. 164),
I
is an integer.
A1
and
A2
are
FLOATS
. The number 5 is loaded
As FLOAT
to add efficiently with
constant ID, which was compiled
As FLOAT
for the previous expression to avoid
an inefficient runtime conversion from
LONG
to
FLOAT
before each floating
point addition.
7.8.3.10.4
Logical Expressions
Measurements can indicate absence or presence of an event.
For example, an RH
measurement of 100% indicates a condensation event such as fog, rain, or dew.
The CR6 can render the state of the event into binary form for further processing,
so i.e the event is either occurring (true), or the event has not occurred (false).
True = -1, False = 0
In all cases, the argument
0
is translated as
FALSE
in logical expressions; by
extension, any non-zero number is considered "non-FALSE."
However, the
164