Add complex number Descriptor

[Euler-37]

add descriptor to dispay format complex data
(1) format(CF10.4) <-format("(",F10.4,",",F10.4,")")
(2) format(CES12.5) <-format("(",ES12.5,",",ES12.5,")")
(3) Experimental , add python like format
format(ZF10.4) <- format(F10.4,"+",F10.4,"j")
format(ZES12.5) <-format(ES12.5,"+",ES12.5,"j")

[certik]

I think both of these could be implemented in stdlib first.

[Euler-37]

I think both of these could be implemented in stdlib first.

Yes , (feature) disp they prepare to add function disp ,It is a good feature.

[klausler]

Examples (1) and (2) are surprising omissions in Fortran; implementing them would be straightforward and valuable. List-directed and NAMELIST output of COMPLEX already exist in the language in this parenthesized form, with an adjustable comma character too.

Example (3) is more dubious. The FORMAT edit descriptor "Z" is already taken for another purpose, and emitting a form of complex output that differs from those used in Fortran source code is less compelling.