These libraries can read an xml document into fortran or write fortran data to xml. For more documentation on xml see wikipedia.
To improve performance a special attribute has been defined for tags:
<tag type="realdata">. When this attribute is the data in this tag will be
treated as a huge chunck of real data. The dimensions of this block have to be
set by the attributes size=, which indicates the number of lines and width=,
which indicates the number of columns.
Use the -xml option when running pamadm for the modules to be compiled.
The libraries can be accesed by including in the fortran code
USE xml_parser
A given XML document is read at once to memory, from where any tag can easily
be accessed.
The next thing to be done is to declare a pointer to an XML document.
type(xml_tag):: tag
Then the following functions can be called:
Starts an new xml document tree, with name treename. Returns a pointer to the xml tree
Reads a file named with filename, containing an xml document into the document tree with name treename (name is used if treename is missing). Returns a pointer to the xmltree.
Writes the document tree treename into an xml file, with filename.
Removes the document tree treename from memory, returns the null-pointer.
Sets the pointer xml_tag to the next tag with name and having optionally the attribute name to nameattribute (ie. <name name=”nameattribute” ... >). If name is “” or missing then the pointer xml_tag is set to the next subtag of the last non empty search name (or the entire document). The function returns true or false depending on wether a next tag is found. So in order to search all the subtags of say the tag ‘grid’ it’s sufficient to use:
type(xml_tag),pointer:: tag
!
tag=>open('xmlfile')
do while(xml_tag_next(tag,'grid'))
do while(xml_tag_next(tag))
... code ...
end do
end do
tag=>xml_close('xmlfile')
returns the name of the tag or it sets the name of a tag.
returns the value of an tag attribute, or sets it. xml_name returns the name of the tag or it sets the name of a tag.
Returns a pointer to an array containing the character of real data that is stored in the tag pointed to by xml_tag. So usage could be
character,pointer:: char_data(:)
real,pointer:: real_data(:,:)
!
... some code ...
char_data=>xml_get_data(tag)
real_data=>xml_get_data(tag)
... more code ...
The function returns null() if no data is stored.
Writes real or character data to the current tag stored in the tag pointed to by xml_tag. So usage could be
character(len=...),pointer:: char_data(:)
character(len=...):: string
real:: real_data(:,:)
!
... some code ...
call xml_add_data(tag,char_data)
call xml_add_data(tag,string)
call xml_add_data(tag,real_data)
... more code ...
If real data is entered to this function a tag will automatically be treated as a chunck of realdata. Meaning that it wil automatically get the attributes type=*real_data*, size and with (ie. <tag type=”realdata” size= width= >).
Adds to the current xml_tag a new tag with name tagname and returns a pointer to the new tag.
Returns the a pointer to the tag that contains the current tag. to the new tag.
Typical use to write an xml document: As an example we write an HTML table:
use xml_parser
type(xml_tag),pointer:: tag
!
tag=>xml_open('mydoc.xml')
tag=>xml_tag_open(tag,'table')
tag=>xml_tag_open(tag,'tr')
tag=>xml_tag_open(tag,'td')
... set up a string or data ...
call xml_attribute(tag,'valign','20')
call xml_attribute(tag,'textcolor','#AAAAAA')
call xml_add_data(tag,string)
tag=>xml_tag_close(tag)
tag=>xml_tag_open(tag,'td')
... similar ...
tag=>xml_tag_close(tag)
... etc ...
tag=>xml_tag_close(tag)
tag=>xml_tag_close(tag)
xml_write('mydoc.xml')
xml_close('mydoc.xml')
Typical use to read an xml document: Let’s get all the coordinates of a bunch of atoms:
use xml_parser
type(xml_tag),pointer:: tag
real,pointer:: coordinates(:,:)
character(len=...):: atom_name
!
tag=>xml_open('mydoc.xml')
tag=>xml_read('mydoc.xml')
do while(xml_get_next(tag,'atom')
atom_name=xml_attribute(tag,'name')
do while(xml_get_next(tag))
if (xml_name(tag)=='coordinates') then
coordinates=>xml_get_data(tag)
write(*,*) 'Coordinates of ',atom_name,':',coordinates
end if
end do
end do
xml_close('mydoc.xml')
This file is included in the fortran code and contain settings that fine-tune the performance and layout. The variables are described inside the file.