Specifications

4.4 Method for Specifying Data
4.4.4 Single-precision real/double-precision real data
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PROGRAM CONFIGURATION
(3) Precautions for when setting input values of single-precision real data/double-precision real
data from the programming tool
(a) Single-precision real
Single-precision real data are processed as 32-bit single precision in the programming
tool, and thus the number of significant figures becomes approximately 7. If the input
value of single-precision real data exceeds 7 digits, the 8th digit is rounded.
If the value after the rounding exceeds a value between -2147483648 and 2147483647,
an operation error occurs.
(b) Double-precision real
Double-precision real data are processed as 64-bit double precision in the programming
tool, and thus the number of significant figures becomes approximately 15. If the input
value of double-precision real data exceeds 15 digits, the 16th digit is rounded.
If the value after the rounding exceeds a value between -2147483648 and 2147483647,
an operation error occurs.
Example 1: When '2147483647' is set for the input value
8th digit '6' is rounded.
The value is handled as '2147484000'.
Example 2: When 'E1.1754943562' is set for the input value
8th digit '3' is rounded.
The value is handled as 'E1.175494'.
Example 1: When '2147483646.12345678' is set for the input value
16th digit '6' is rounded.
The value is handled as '2147483646.12346'.
Example 2: When 'E1.7976931348623157+307' is set for the input value
16th digit '5' is rounded.
The value is handled as 'E1.79769313486232+307'.