incorrect results with trig functions

[twenty]

Mikroe, please have a look at the program below. The result of a trig calculation appears to be incorrect. Any help would be appreciated.
Regards,

(Mikrobasic Pro for AVR, XMEGA 128a1)

program MyProject1

' Declarations section
const R= 6371000
dim lat1 as double
dim lat2 as double
dim lon1 as double
dim lon2 as double
dim distance as double

main:
lat1=-33*PI/180
lat2=-34*pi/180
lon1=151*pi/180
lon2=152*pi/180
'distance = acos(sin(lat1)*sin(lat2) + cos(lat1)*cos(lat2)*cos(lon2-lon1))*R
distance=sin(lat1) ' -5.446390E-001 should be 0.00100522 !!!!!!!!!!
nop

end.

[twenty]

The ARM compiler for mikrobasic pro behaves the same way

[filip]

Hi,

It behaves the same way, because the argument (-33*PI/180) is basically the -33 degrees, so you are actually calculating the sin(-33).

Regards,
Filip.

[twenty]

You are correct. Thanks for your response