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From: "=?big5?B?bWtlcm9wcGkgxVGk/atnrFA=?=" <m_keroppi AT hotmail DOT com>
To: <djgpp AT delorie DOT com>
Subject: Re: Inverse trigonometry functions in Djgpp
Date: Thu, 30 Dec 1999 11:18:23 -0500
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Reply-To: djgpp AT delorie DOT com

In radians, multiply by 360, divide by 2pi

==
Atan () - don't work!
Here is a bit of my code:

float direction;

direction = atan ( 120 / 90 );
printf ("%f", direction");

And output is this:
0.927295

But with calculator it is:
tan^-1 (120 / 90) = 53.1301023...

Is atan () right inverse tan function?

Greetings,
Jarkko DOT Kahkonen AT mbnet DOT REMOVETHAT DOT fi