Language and Conventions Overview | Introduction to GPAs
The access type of a GPA symbol determines the type of access operation which can be performed. GPAs contain data which can be read, written over, or used to set the value of other GPAs. If a GPA has READ/WRITE access, you can obtain its value, or write a new value to it. To maintain the integrity of the data base, the value of some GPAs cannot be changed. In this case the GPA will have a READ ONLY access type. Some GPAs are used only to assign values to other GPAs. In this case the GPA will have a CONSTANT access type.
|
Access Type |
Description |
|
Read Only (RO) |
Value may be obtained but not altered. |
|
Read/Write (RW) |
Value may be obtained or altered. |
|
Constant (C) |
Value may be used to set other GPAs. |
The READ capability for GPA symbols, implies that the value of the GPA being addressed may be obtained (fetched from the system) and used for various purposes in a GRIP program.
STRING/PNAME(30),USERID(30)
$$
$$ OBTAIN THE CURRENT
PARTNAME
$$
PNAME = &PNAME
$$
$$ OBTAIN THE USER ID
USERID =
&USERID
The WRITE capability for GPA symbols, implies that the value of the GPA being addressed may be changed (altered) by a GRIP program.
$$ SET TOLERANCE TYPE
TO GPA CONSTANT &NOTOL
$$
&TOLER=&NOTOL
$$
$$ SET THE
DIMENSIONAL FRACTION TYPE TO DECIMAL
$$
&FTYPE=&DECIM
$$
$$
SET THE NUMBER OF DIMENSIONAL DECIMAL
$$ PLACES
$$
&DDECPL=4
The GPAs &TOLER, &FTYPE, and &DDECPL all have an access type of READ/WRITE allowing them to be assigned values in a program.