[texhax] pgf: putting arrow on parametric curve

[Philip TAYLOR]

William F Hammond wrote:

> Victor Ivrii <vivrii at gmail.com> writes:
> 
>> When I put an arrowhead on the end parametric curve it is
>> pointing up rather than along curve. Is there a good way
>> to put arrow in the correct direction automatically?
> 
> How is the parametric curve created in the tex file?
> Picture environment?  Graphicx inclusion?  MetaPost?

PGF (see subject).
Philip Taylor