CC78K4 Datasheet, PDF (259/523 Pages) NEC – CC78K4 Ver.2.30 or Later, C Compiler Language

CHAPTER 10 LIBRARY FUNCTIONS
7-27 atan2f
Mathematical Functions
FUNCTION
atan2f finds atan of y/x.
HEADER
math.h
FUNCTION PROTOTYPE
float atan2f (float y, float x);
Function
atan2f
Arguments
x ... Numeric value to perform
operation
y ... Numeric value to perform
operation
Return Value
Normal ... atan of y/x
When both x and y are 0 or a
value whose y/x cannot be
expressed, or either x or y is
NaN, both x and y are ±∞ ...
NaN
When underflow occurs ...
Non-normalized number
EXPLANATION
• Calculates atan (range between –π and +π) of y/x. When both x and y are 0 or the value whose y/x cannot
be expressed, or when both x and y are infinite, NaN is returned and EDOM is set to errno.
• When either x or y is non-numeric, NaN is returned.
• If an underflow occurs as a result of the operation, a non-normalized number is returned.
User’s Manual U15556EJ1V0UM
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