xslt trouble with xsl:if

[z1]

hi-

i am fooling around with soap and weather templates.
for some reason either this if or select is failing.
i am very new to xml and found this code at another site.
i can show you the xml and then the xslt sample code that is not matching.
please look and if it jumps right off the page give me a tip on why it didnt
select the data.
i think for most xslt people this will be easy. i want the if to work if it
is null because
the weather service may return null for an attribute.

from the government weather service:
<weather time-layout="k-p24h-n5-1">
<name>Weather Type, Coverage, and Intensity</name>
<weather-conditions weather-summary="Increa sing Clouds"/>
<weather-conditions weather-summary="Partly Cloudy"/>
<weather-conditions weather-summary="Partly Cloudy"/>
<weather-conditions weather-summary="Mostly Sunny"/>
<weather-conditions weather-summary="Chance Rain Showers">
<value coverage="chanc e" intensity="ligh t" weather-type="rain
showers" qualifier="none "/>
</weather-conditions>
</weather>
from a sample template i found:
<xsl:template name="weather">
<xsl:param name="position" />
<xsl:if
test="/dwml/data/parameters/weather/weather-conditions[position()=$pos ition]/@weather-summary
!=''">
<xsl:value-of
select="/dwml/data/parameters/weather/weather-conditions[position()=$pos ition]/@weather-summary"/>
</xsl:if>
</xsl:template>

other parts of the templates are generating output (not formatted yet
though)
assuming that the path is correct and it looks like it is, why wont this
match?
@weather-summary is the attribute that has a value associated with it that
is not null.
the path from the root looks ok....

i want to get into learning a little bit more about xml and xslt.
i have a book on it and am currently studing a css book too.
i like the fact that when i combine all the templates with html i can have
it output
the results formatted. i need to get better at the xslt processing.

thanks very much.
i hope you are enjoying the weekend too.
jim (website - 3rdshiftcoder.c om)

[Peter Flynn]

z1 wrote:

hi-

i am fooling around with soap and weather templates.
for some reason either this if or select is failing.
i am very new to xml and found this code at another site.
i can show you the xml and then the xslt sample code that is not matching.
please look and if it jumps right off the page give me a tip on why it didnt
select the data.
i think for most xslt people this will be easy. i want the if to work if it
is null because
the weather service may return null for an attribute.

from the government weather service:
<weather time-layout="k-p24h-n5-1">
<name>Weather Type, Coverage, and Intensity</name>
<weather-conditions weather-summary="Increa sing Clouds"/>
<weather-conditions weather-summary="Partly Cloudy"/>
<weather-conditions weather-summary="Partly Cloudy"/>
<weather-conditions weather-summary="Mostly Sunny"/>
<weather-conditions weather-summary="Chance Rain Showers">
<value coverage="chanc e" intensity="ligh t" weather-type="rain
showers" qualifier="none "/>
</weather-conditions>
</weather>
from a sample template i found:
<xsl:template name="weather">
<xsl:param name="position" />
<xsl:if
test="/dwml/data/parameters/weather/weather-conditions[position()=$pos ition]/@weather-summary
!=''">

Depending on how the incoming data is handled (parsed as well-formed
only, or validated), position() may evaluate to one of two things:

a) what you intuitively expect (if you're used to normal text document
markup (HTML, DocBook, TEI, etc): the numeric position of the
weather-conditions *element node* among its siblings (eg for
@weather-summary='Partly Cloudy' this would be "2" and "3");

b) what you don't expect (unless you came to XML via the "data-only"
route): the numeric position of the matching node among *all* types of
siblings, including the "name" element and the (otherwise irrelevant)
white-space between the weather-conditions elements (eg for
@weather-summary='Partly Cloudy' this would be "6" and "8").

I'm unclear why it would want to identify the weather-conditions element
by position anyway.

The reliable way of matching location-among-siblings is to use
[count(preceding-sibling::weathe r-conditions)+1=$ position]

<xsl:value-of
select="/dwml/data/parameters/weather/weather-conditions[position()=$pos ition]/@weather-summary"/>
</xsl:if>
</xsl:template>

other parts of the templates are generating output (not formatted yet
though)
assuming that the path is correct and it looks like it is, why wont this
match?

Use xsl-message and xsl:value-of to output the actual value of $position
to the console during execution so you can debug it.

@weather-summary is the attribute that has a value associated with it that
is not null.
the path from the root looks ok....

You haven't shown us the whole document, so we'll take it on trust that
there is a containing structure reflecting /dwml/data/parameters

i want to get into learning a little bit more about xml and xslt.
i have a book on it and am currently studing a css book too.
i like the fact that when i combine all the templates with html i can have
it output
the results formatted. i need to get better at the xslt processing.

Dave Pawson's excellent XSL FAQ (http://www.dpawson.co.uk/xsl/), and
Mulberry's XSL-LIST mailing list
(http://www.mulberrytech.com/xsl/xsl-list/index.html) are your friends.

///Peter
--
XML FAQ: http://xml.silmaril.ie/

[z1]

Hi Peter -

thanks very much for the response.
i need to practice more.
i will save your post and can come
back to it a little later.

i kind of get things but need more work.
thanks for the list of resources at the end
of your post.

jim

"Peter Flynn" <pe********@m.s ilmaril.iewrote in message
news:67******** *****@mid.indiv idual.net...

z1 wrote:

>hi-

i am fooling around with soap and weather templates.
for some reason either this if or select is failing.
i am very new to xml and found this code at another site.
i can show you the xml and then the xslt sample code that is not
matching.
please look and if it jumps right off the page give me a tip on why it
didnt
select the data.
i think for most xslt people this will be easy. i want the if to work if
it
is null because
the weather service may return null for an attribute.

from the government weather service:
<weather time-layout="k-p24h-n5-1">
<name>Weather Type, Coverage, and Intensity</name>
<weather-conditions weather-summary="Increa sing Clouds"/>
<weather-conditions weather-summary="Partly Cloudy"/>
<weather-conditions weather-summary="Partly Cloudy"/>
<weather-conditions weather-summary="Mostly Sunny"/>
<weather-conditions weather-summary="Chance Rain Showers">
<value coverage="chanc e" intensity="ligh t" weather-type="rain
showers" qualifier="none "/>
</weather-conditions>
</weather>
from a sample template i found:
<xsl:templat e name="weather">
<xsl:param name="position" />
<xsl:if
test="/dwml/data/parameters/weather/weather-conditions[position()=$pos ition]/@weather-summary
!=''">

Depending on how the incoming data is handled (parsed as well-formed
only, or validated), position() may evaluate to one of two things:

a) what you intuitively expect (if you're used to normal text document
markup (HTML, DocBook, TEI, etc): the numeric position of the
weather-conditions *element node* among its siblings (eg for
@weather-summary='Partly Cloudy' this would be "2" and "3");

b) what you don't expect (unless you came to XML via the "data-only"
route): the numeric position of the matching node among *all* types of
siblings, including the "name" element and the (otherwise irrelevant)
white-space between the weather-conditions elements (eg for
@weather-summary='Partly Cloudy' this would be "6" and "8").

I'm unclear why it would want to identify the weather-conditions element
by position anyway.

The reliable way of matching location-among-siblings is to use
[count(preceding-sibling::weathe r-conditions)+1=$ position]

> <xsl:value-of

select="/dwml/data/parameters/weather/weather-conditions[position()=$pos ition]/@weather-summary"/>
</xsl:if>
</xsl:template>

other parts of the templates are generating output (not formatted yet
though)
assuming that the path is correct and it looks like it is, why wont this
match?

Use xsl-message and xsl:value-of to output the actual value of $position
to the console during execution so you can debug it.

>@weather-summary is the attribute that has a value associated with it
that
is not null.
the path from the root looks ok....

You haven't shown us the whole document, so we'll take it on trust that
there is a containing structure reflecting /dwml/data/parameters

>i want to get into learning a little bit more about xml and xslt.
i have a book on it and am currently studing a css book too.
i like the fact that when i combine all the templates with html i can
have
it output
the results formatted. i need to get better at the xslt processing.

Dave Pawson's excellent XSL FAQ (http://www.dpawson.co.uk/xsl/), and
Mulberry's XSL-LIST mailing list
(http://www.mulberrytech.com/xsl/xsl-list/index.html) are your friends.

///Peter
--
XML FAQ: http://xml.silmaril.ie/

[z1]

Hi again Peter-

I am finally getting this stuff better.

What had me stuck was that somehow the file i had copied from the government
web server for the weather wasnt quite right. you can put in all the xpath
and
xslt you want but if the xml file is broken that you are basing it on you
are
nowhere. i must not have copied it just right or hit a key by mistake
and saved it.

i found that if i keep the command line open in windows and run
saxon after i make changes in the phpedit environment it is blazing
fast and gives me good tips on where to fix the problems.

i wont need that other persons code once i get going.
i am going to make the weather forecast fancier on my site when
i get the time.

thanks so much for helping,
jim