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How Functions Use fimath

Functions that use then discard attached fimath

FunctionsNote
conv, filterError if attached fimaths differ.
mean, median—

Functions that ignore and discard attached fimath

FunctionsNote
accumneg, accumpos

  • By default, use Floor rounding method and Wrap overflow

add, sub, mpy

  • Override and discard any fimath objects attached to the input fi objects

  • Uses the fimath from input, F, as in add(F, a, b)

CORDIC functions (see CORDIC Algorithms in MATLAB)

CORDIC functions use their own internal fimath:

  • Rounding Mode – Floor

  • Overflow Action – Wrap

mod—
qr—
quantizeUses the math settings on the quantizer object, ignores and discards any fimath settings on the input
Trigonometric functions — atan2, cos, sin—

Functions that do not perform math

FunctionsNote
Built-in Types—int32, int64, int8, uint16, uint32, uint64, uint8Ignore any fimath settings on the input. Always use the rounding method Round when casting to the new data type. The output is not a fi object so it has no attached fimath.
bitsll, bitsra, bitsrlOverflowAction and RoundingMethod are ignored — bits drop off the end.
bitshiftRoundingMethod is ignored, but OverflowAction property is obeyed.