Bug ID: 2299224 "unsimplified result from rectform"

We have the bug report ID: 2299224 "unsimplified result from rectform".

The first issue of this bug report has gone, we get a correct result
with rectform:

(%i1) rectform(log(x+%i*y));
(%o1) log(y^2+x^2)/2+%i*atan2(y,x)

The second issue is, that the option variable logarc does not work with
rectform. The reason is, that the global variable $logarc is set to nil
in the routine risplit in rpart.lisp. If we cut out this setting we get
the following:

(%i2) rectform(log(x+%i*y)),logarc;
(%o2) log((%i*y+x)/sqrt(y^2+x^2))+log(y^2+x^2)/2

The problem is, that rectform now no longer returns the standard form
realpart(expr)+%i*imagpart(expr). I am not sure and I have no examples,
but it might be possible, that we run into problems, if rectform does
not return the expected standard form.

I think, because of this behavior the option variable $logarc is set to
nil in the routine risplit.

Furthermore, I think, we should not change the setting of $logarc, but
add a remark to the documentation that inverse trigonometric functions
are not simplified to a representation in terms of logarithmic functions
when in rectform.

Dieter Kaiser