Vector Basic Interpreter Basic 80, Reference Manual, Page: 180 / 190

TRON/TROFF
In order to
switch must
ignored and use TRON/TROFF, the
/0
compilation
be used. Otherwise, TRON and TROFF are
a warning message is generated.
11. FOR/NEXT and WHILE/WEND
FOR/NEXT and WHILE/WEND loops
must be statically
nested.
12. Double Precision Transcendental Functions
SIN, COS, TAN, SQR,
LOG, and EXP return doubIe
precision results if given a double precision
argument. Exponentiation with double precision
operands will return a double precision result.
turing expression evaluation, the operands of each operator
are converted to the same type, that of the most precise
operand. For example,
causes J% to be converted to single precision and added to
Al.
This result is converted to double precision and added
to
Qt.
The Compiler is more limited than the interpreter in
handling numeric overflow. For example, when run on the
interpreter the following program
I%-20000
J%-20000
K%--30000
M%-I%+J%-K%
yields 10000 for M%. That is, it adds I% to J% and, because
the number is too large, it converts the result into a
floating point number. K% is then coverted to floating
point and subtracted. The result of 10000 is found, and is
converted back to integer and saved as M%.
The compiler, however, must make type conversion decisions
during compilation. It cannot defer until the actual values
are k.'"1own.Thus, the compiler would generate code to
perform the entire operation in integer mode. If ~~e /0
switch were set, the error would be detected. Otherwise, an
incorrect answer would be produced.
In order to produce optimum efficiency in ~~e compiled
program, the compiler may perform any number of valid
algebraic transformations before generating the code. For