TMS320F28035: TMS320F28035: what is the name of the arctan function in software library, ? what is the input range of the arctan function ? if the arctan function output is per-unit ? if there are some example of how to use the arctan function ? many

Andrew,

I presume you are asking about the C run-time support library. Let me know if that is not the case.

Arctangent is supported by the standard C functions:
atan() for double
atanf() for float
atnl() for long double

You will need to include the header file math.h to have access to these. In all cases the input range is +/- infinity, the output is in radians. For example, try:

float val = -10.25f;
volatile float y = 0.0f;

main()
{

do {
val += 0.25f;
y = atanf(val);
} while (val <= 10.0f);

y should change between about -pi and +pi.

Regards,

Richard