SIN and COS mixed up?

[igoatm]

Not sure if I am going dappy but whilst working on some matrix math it seems that the returned values for SIN(x) and COS(X) are mixed up ie COS(x) is returning SIN(X) values and SIN(X) is returning COS(X) values

Nop It is just me going dappy mixed my x n y up in ATN2 function

' ATN2()
' Needed as bacon only offers the dule quadrent ATN
' for positive none zero x
' this was built using the wekipida define
' it seems to be the most standadised version
' and is the same define as used by the c complier
' USED WIKIPEDIA DEFINITION
' x > 0 = ATN(y/x)
' y >= 0, x < 0 ATN(y/x)+PI
' y < 0, x < 0 ATN(y/x)-PI
' y > 0, x = 0 +PI/2
' y < 0, x = 0 -PI/2
' y = 0, x = 0 "UNDEFINED"
FUNCTION ATN2(FLOATING x, FLOATING y)
' --------------------
LOCAL rn TYPE float
IF x EQ 0 THEN
IF y EQ 0 THEN
rn = 0
ELSE
IF y LT 0 THEN
rn = -PI/2
ELSE
rn = PI/2
ENDIF
ENDIF
ELSE
IF x GT 0 THEN
rn = ATN(y/x)
ELSE
IF y GE 0 THEN
rn = ATN(y/x)+PI
ELSE
rn = ATN(y/x)-PI
ENDIF
ENDIF
ENDIF
RETURN rn
END FUNCTION

[vovchik]

Dear igoatm,

I was just going to write to tell you that BaCon uses the standard C math functions cos() and sin(), so if there is something wrong there, it would have been picked up decades ago.


' compare BaCon and native C functions
PRINT cos(45)
PRINT sin(45)
PRINT COS(45)
PRINT SIN(45)


I am glad you found the bug in your source. You had me worried for a few seconds.

With kind regards,
vovchik