Op 31-03-2020 om 01:18 schreef Graydon:

On Mon, Mar 30, 2020 at 11:16:23PM +0200, Ben Engbers scripsit: [snip]

...

For "probleem", the idf should be calculated as ln($count/703). Since there are 1780 nodes this would result in 0.929011751. I tried to exten the 'let $idf' line with: => array:for-each(function($idf) {array:append($idf, math:log($count div $idf[2]) )}) which should result in ["probleem", 703, 0.929011751]

but no mather what I do, every time I get this error: [XPTY0004] Cannot promote (array(xs:anyAtomicType))+ to array(*): ([ "probleem", 703 ], [ "opgelost.", 248 ], ...).

The errors says you're trying to feed a sequence of arrays to an array function; maybe you want ! where you have => ?

-- Graydon

Hi, Upon your remark about feeding a sequence of arrays, I first tried to apply 'for-each' instead of 'array:for-each'. Alas, that didn't help ;-(, the error was still the same. I then tried to understand what you mean with the '!'. In the book from Priscilla Walmsley, the ! is mentioned as a simple map operator. How is that related to this problem? Cheers, Ben

Hi,

=> means "take the thing on the left and substitute it for the first parameter of the function on the right, so I thought it meant "The first parameter on the right will be subsituted with the thing on the left"?

('weasels') => replace('weasels','mustelids') works

('weasels','badgers') => replace('weasels','mustelids') DOES NOT work

This is because a one-item sequence can be treated as the single string value the first parameter of replace() requires, but a greater-then-one-item sequence can't be. (This one gives you "item expected, sequence found" if you try it from the GUI.)

The following is quite similar to the 'piping' mechanism in R. I'll start experimenting with it. Thanx, Ben

! means "take each item of the sequence on the left and pass it to the thing on the right in turn", so

('weasels','badgers') ! replace(.,'weasels','mustelids') works.

(note that replace() got its first parameter back as the context item dot.)

so if you take

=> array:for-each(function($idf) {array:append($idf,math:log($count div $idf[2]) )})

and replace it with ! array:for-each(.,function($idf) {array:append($idf,math:log($count div $idf[2]) )})

(note the context-item dot!)

you should at least get a different error message.

-- Graydon

Hi, For (my personal) clarity, I have split up the original function in two parts: declare function local:step_one($nodes as node()*) as array(*)* { let $text := for $node in $nodes return $node/text() => tokenize() => distinct-values() let $idf := $text => tidyTM:wordCount_arr() return $idf }; In local:step_one(), I first create a sequence with the distinct tokens for each $node. All the sequences are joined in $text. I then call wordCount_arr to count the occurences of each word in $text: declare function tidyTM:wordCount_arr( $Words as xs:string*) as array(*) { for $w in $Words let $f := $w group by $f order by count($w) descending return ([$f, count($w)]) } ; I would say that tidyTM:wordCount_arr returns a sequence of arrays but I am not certain if I have specified the correct return-type? Calling local:step_one(tidyTM:remove_Stopwords($nodes, "Stp", $Stoppers)) returns: ["probleem", 703] ["opgelost.", 248] .... I had hoped that calling the following local:wordFreq, would add the idf to each element but instead I get an error declare function local:wordFreq_idf($nodes as node()*) as array(*) { let $count := count($nodes) let $idf := local:step_one($nodes) let $result := for-each( $idf, function($z) {array:append ($z, math:log($count div $z(2) ) ) } ) return $result }; [XPTY0004] Cannot promote (array(xs:anyAtomicType))+ to array(*): $idf := ([ "probleem", 703 ], [ "opgelost.", 248 ], ...). Cheers, Ben Op 31-03-2020 om 16:29 schreef Martin Honnen:

So does the working function return a sequence of arrays? That doesn't match the   as array(*) return type declaration, it seems.

What does tidyTM:wordCount_arr() return, a single array (of atomic items)?