matlab atan2
atan2
>> atan2(4,-3)
ans =
2.2143
>>
>> atan2(-5,-5)*180.0/3.1415926
ans =
-135.0000
>>
#######################
QQ 3087438119
>> atan2(4,-3)
ans =
2.2143
>>
>> atan2(-5,-5)*180.0/3.1415926
ans =
-135.0000
>>
#######################