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From Niclas Hedhman <nic...@hedhman.org>
Subject Re: Request for correcting wrong Information on website
Date Thu, 21 Apr 2016 01:15:22 GMT
Thanks, but you are unfortunately addressing the wrong community / mailing
list.

Please contact the Apache Commons project directly. See
http://commons.apache.org/mail-lists.html

Cheers
Niclas

On Thu, Apr 21, 2016 at 4:51 AM, . <mdzafir.alvi.1@gmail.com> wrote:

> ---------- Forwarded message ----------
> From: . <mdzafir.alvi.1@gmail.com>
> Date: Thu, Apr 21, 2016 at 2:35 AM
> Subject: Request for correcting wrong Information on website
> To: apache@apache.org
>
>
> Dear site admin ,
> I was browsing this page below :
> https://commons.apache.org/proper/commons-math/userguide/complex.html
>
> Between /* */ I am copy pasting some lines from the page . After this /**/
> mark i will post error and corrections
>
> /*
>
> The Complex class provides basic unary and binary complex number
> operations. These operations provide the means to add, subtract, multiply
> and divide complex numbers along with other complex number functions
> similar to the real number functions found in java.math.BigDecimal:
>
> Complex lhs = new Complex(1.0, 3.0);
> Complex rhs = new Complex(2.0, 5.0);
>
> Complex answer = lhs.add(rhs);       // add two complex numbers
>         answer = lhs.subtract(rhs);  // subtract two complex numbers
>         answer = lhs.abs();          // absolute value
>         answer = lhs.conjugate(rhs); // complex conjugate
>
> 7.3 Complex Transcendental Functions
>
> Complex
> <
> https://commons.apache.org/proper/commons-math/apidocs/org/apache/commons/math3/complex/Complex.html
> >
> also
> provides implementations of serveral transcendental functions involving
> complex number arguments. These operations provide the means to compute the
> log, sine, tangent, and other complex values :
>
> Complex first  = new Complex(1.0, 3.0);
> Complex second = new Complex(2.0, 5.0);
>
> Complex answer = first.log();        // natural logarithm.
>         answer = first.cos();        // cosine
>         answer = first.pow(second);  // first raised to the power of second
>
> */
>
>
>
>
>
> First error :
>
> see the line :   ------> answer = lhs.abs();          // absolute value
>
>
>
> answer was declared in complex previously , so you must capture the
> reply of lhs.abs() to a double variable
>
> correct:
>
> double answer = lhs.abs();
> or
> double ans = lhs.abs(); // we have already declared a variable name
> //answer , so save this with a variable of different name
>
>
> Error 2 :
>
> see this line -->
>
>
> answer = lhs.conjugate(rhs); // complex conjugate
>
>
> Note that , Conjugate is a one input function , If z = 2+3i is a
> complex , conjugate is 2-3i , Here you pushed 2 complex ( lhs , rhs )
> instead of one conjugate ( either lhs or rhs ) . So this generates error
>
> Correct :
>
> either :
>
> answer = lhs.conjugate();
>
> or:
>
> answer = rhs.conjugate();
>
> both are correct If you think by chance I am wrong , you can even check
> javadoc of your library , everything was correct there , but the example on
> this web is wrong only. Thats all I had to say. I am a great fan of your
> library Apache Commons Math 3.6.1 I was working on a project , in this
> project I needed to use common math .jar . It helped me a lot by saving
> time of many hard implementations . As a fan , I request you to correct
> this information as soon as possible . Thanks in advanced . - From one of
> your fans - Alvi
>



-- 
Niclas Hedhman, Software Developer
http://zest.apache.org - New Energy for Java

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