How do I use multiple OR operators in XPath - xpath

I am trying to combine three different OR opearators
[FindsBy(How = How.XPath, Using = "[//img[contains(#src,'/BankPayProcessing-Icon.png')]|//span[contains(text(), 'Bank Pay Processing')]|//span[contains(text(), 'BankPay Processing')]")]
However, this is not working. I am not able to figure out why.
Can I get some help please?

The "or" operator in XPath is not "|", it is "or".
The "|" operator forms the union between two node-sets, it cannot be applied to a boolean value (such as the result of (A=B)).
It's easy to be misled when you see something like match="x|y" into thinking it matches "x or y". Actually it matches the union of x and y, that is, anything in the set of all x and y elements.

Related

Power Query - Multiple OR statement with values

I've been doing research on this and I find a plethora of articles related to Text, but they don't seem to be working for me.
To be clear this formula works, I'm just looking to make it more efficient. My formula looks like:
if [organization_id] = 1 or [organization_id] = 2 or [organization_id] = 3 then "North" else if … where organization_id is of type "WholeNumber"
I'd like to simplify this by doing something like:
if [organization_id] in {1, 2, 3} then "North" else if …
I've tried wrapping in Parenthesis, Braces, & Brackets. Nothing seems to work. Most articles are using some form of text.replace function and mine is just a custom column.
Does MCode within Power Query have any efficiencies like this or do I have to write out each individual statement like the first line?
I've had success with the a List.Contains formulation:
List.Contains({1,2,3}, [organization_id])
The above checks if [organization_id] is in the list supplied in the first argument.
In some cases, you may not want to hardcode a list as shown above but reference a table column instead. For example,
List.Contains(TableWithDesiredIds[id_column], [organization_id])

How evaluate concatenated string as indexed XPath expression in VB6

I've built an Xpath expression by concatenating strings in VB6:
strXPath = "xDOC.selectNodes(" & """/GroupType1""" & ").item(" & CStr(i) & ").selectNodes(" & """/OperationStageCollection/OperationStage""" & ").length"
"i" is an integer used to index into
I want to evaluate strXPath to get a loop counter, for example:
n = CInt(strXPath)
n is declared as Integer; strXPath is declared as string. VB6 throws a Type Mismatch error on the above evaluation expression. I must be missing something obvious. How can I evaluate strXPath?
I realize that there may be errors in the XPath expression itself, but I'd like to get the evaluation working in order to debug such possible errors.
Try removing some of the double-quotes:
iLength = xDOC.selectNodes("/GroupType1").item(i).selectNodes("/OperationStageCollection/OperationStage").length
This should return the length property you want, as an Integer.
Then you can use iLength in your loop.
#BRW: both of your questions are very specific, i.e. how to achieve certain results using XPath. But I have the suspicion that if you would explain what (data) you try to retrieve form the XML, commenters might show you ways you didn't think of, e.g. say you want to iterate through all <OperationEvent>s within a <OperationEventCollection>, a single <OperationEvent> can be retrieved by //GroupType1/OperationStageCollection/OperationStage/OperationEventCollection/OperationEvent[1-based-index], e.g. //GroupType1/OperationStageCollection/OperationStage/OperationEventCollection/OperationEvent[1], which results in a single XML node:
<OperationEvent>
<OperationEventDate1>2018-12-16</OperationEventDate1>
<OperationEventCode>5</OperationEventCode>
<OperationEventDate2>2018-05-16</OperationEventDate2>
</OperationEvent>
So instead multiple selectNodes methods, one proper XPath query might yield the desired outcome right away.

xPath union statement with functions

thanks in advance for reading.
I'm using $x() xPath evaluator of Chrome console.
I need to match something shaped like $x("e1 | e2").
In my case:
e1:
(//div[#class='seven columns omega']//form//div[#class='items_left']//text())[2]
e2
(substring-after(//div[#class='seven columns omega']//span[#class='sold_out']/text(),' - '))
They both works in the single way but if i want to combine them I just get stuck in
"Failed to execute 'evaluate'..."
PS The problem is e2 function substring-after, without it the union works.
Any Ideas?
Here are the 2 sources i'm trying to extract:
e1-case
e2-case
Thanks again :)
Based on your comments that you want string values and expect only one of those expressions to find something on the same page you could simply try
var result = $x("string((//div[#class='seven columns omega']//form//div[#class='items_left']//text())[2])") + $x("(substring-after(//div[#class='seven columns omega']//span[#class='sold_out']/text(),' - '))")

mathematica: PadRight[] and \[PlusMinus]

Is there any way that
PadRight[a \[PlusMinus] b,2,""]
Returns
{a \[PlusMinus] b,""}
Instead of
a \[PlusMinus] b \[PlusMinus] ""
?
I believe that i need to somehow deactivate the operator properties of [PlusMinus].
Why do i need this?
I'm creating a program to display tables with physical quantities. To me, that means tables with entries like
(value of a) [PlusMinus] (uncertainty of a)
When i have several columns with different heights, i'm stuffing the shorter ones with "", so i can use Transpose the numeric part of the table.
If the column has more than one entrie, there's no problem:
PadRight[{a \[PlusMinus] b,c \[PlusMinus] d},4,""]
gives what i want:
{a \[PlusMinus] b,c \[PlusMinus] d,"",""}
It is when the column has only one entrie that my problem appears.
This is the code that constructs the body stuffed with "":
If[tested[Sbody],1,
body = PadRight[body, {Length[a], Max[Map[Length, body]]
With
tested[a__] :=
If[Length[DeleteDuplicates[Map[Dimensions, {a}]]] != 1, False,
True];
, a function that discovers if is arguments have the same dimension
and
a={Quantity1,Quantity2,...}
Where the quantities are the one's that i want on my table.
Thanks
First you need to be aware of that any expression in Mathematica is in the form of Head[Body]
where body may be empty, a single expression or a sequence of expressions separated by commas
Length operate on expressions, not necessarily lists
so
Length[PlusMinus[a,b]]
returns 2 since the body of the expression contains to expressions (atoms in this case) that are a and b
Read the documentation on PadRight. The second argument define the final length of the expression
so
PadRight[{a,b},4,c] results with a list of length 4 with the last two elements equal to
PadRight[{a,b},2,c] results with the original list since it is already of length 2
Therefore
PadRight[PlusMinus[a,b],2,anything] just returns the same PlusMinus[a,b] unchanged since it is already of length 2
so, youר first example is wrong. You are not able to get a result with head List using PadRight when you try to pad to an expression with head PlusMinus
There is no problem of executing
PadRight[PlusMinus[a,b],3,""]
but the result looks funny (at best) and logically meaningless, but if this is what you wanted in the first place you get it, and following my explanations above you can figure out why
HTH
best
yehuda

Recursively (?) compose LINQ predicates into a single predicate

(EDIT: I have asked the wrong question. The real problem I'm having is over at Compose LINQ-to-SQL predicates into a single predicate - but this one got some good answers so I've left it up!)
Given the following search text:
"keyword1 keyword2 keyword3 ... keywordN"
I want to end up with the following SQL:
SELECT [columns] FROM Customer
WHERE
(Customer.Forenames LIKE '%keyword1%' OR Customer.Surname LIKE '%keyword1%')
AND
(Customer.Forenames LIKE '%keyword2%' OR Customer.Surname LIKE '%keyword2%')
AND
(Customer.Forenames LIKE '%keyword3%' OR Customer.Surname LIKE '%keyword3%')
AND
...
AND
(Customer.Forenames LIKE '%keywordN%' OR Customer.Surname LIKE '%keywordN%')
Effectively, we're splitting the search text on spaces, trimming each token, constructing a multi-part OR clause based on each token, and then AND'ing the clauses together.
I'm doing this in Linq-to-SQL, and I have no idea how to dynamically compose a predicate based on an arbitrarily-long list of subpredicates. For a known number of clauses, it's easy to compose the predicates manually:
dataContext.Customers.Where(
(Customer.Forenames.Contains("keyword1") || Customer.Surname.Contains("keyword1")
&&
(Customer.Forenames.Contains("keyword2") || Customer.Surname.Contains("keyword2")
&&
(Customer.Forenames.Contains("keyword3") || Customer.Surname.Contains("keyword3")
);
but I want to handle an arbitrary list of search terms. I got as far as
Func<Customer, bool> predicate = /* predicate */;
foreach(var token in tokens) {
predicate = (customer
=> predicate(customer)
&&
(customer.Forenames.Contains(token) || customer.Surname.Contains(token));
}
That produces a StackOverflowException - presumably because the predicate() on the RHS of the assignment isn't actually evaluated until runtime, at which point it ends up calling itself... or something.
In short, I need a technique that, given two predicates, will return a single predicate composing the two source predicates with a supplied operator, but restricted to the operators explicitly supported by Linq-to-SQL. Any ideas?
I would suggest another technique
you can do:
var query = dataContext.Customers;
and then, inside a cycle do
foreach(string keyword in keywordlist)
{
query = query.Where(Customer.Forenames.Contains(keyword) || Customer.Surname.Contains(keyword));
}
If you want a more succinct and declarative way of writing this, you could also use Aggregate extension method instead of foreach loop and mutable variable:
var query = keywordlist.Aggregate(dataContext.Customers, (q, keyword) =>
q.Where(Customer.Forenames.Contains(keyword) ||
Customer.Surname.Contains(keyword));
This takes dataContext.Customers as the initial state and then updates this state (query) for every keyword in the list using the given aggregation function (which just calls Where as Gnomo suggests.

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