i am trying the inverse tangent function in processing java,

i am using the atan(float) function,

when i use a paramater around 100 / 70 i am getting the wrong result,

this is true for atan(100 / 75), atan(100 / 80) and so on…

converted to degrees, it always returns 45 degrees, which it does not on the windows calculator.

am i doing something wrong or is this not the function i am looking for when needing an inverse tangent?

thanks in advance