could I call a Sub since Expressions

[#1]

Hi experts,

I han a sub in the Script área, this sub can I call in a Expression?

Best regards.

[Anonymous]

no, you can't execute backend function from frontend (macro excepted)

[#3]

well in that case,

could  I set a variable for axample selecting a value from list box?

best regards

[jaimeaguilar · Accepted solution]

Hi,

you can create variables with parameters, so you can have something like "user defined functions" within charts.

An easy example would be something like this:

Let's say your formula is Sum({$<Product={'$1'}>} Sales). In this case the '$1' part, will be calculated until there is some interaction with an external event (like a user selecting one or more products from a listbox). It is important to note that your "dynamic" variable cannot be precalculated, otherwise it won't work correctly. This means that when you create your variable you should not include a = at the beginning of your expression.

Then when calling this variable you need to use the following syntax: $(VariableName(Parameter1, parameter2, parameterN)). Just like in a sub you can define 1 or any number of parameters.

This QlikView Feature allows you to reuse a single variable for many different scenarios and to make your variables more dynamic,

regards

[jaimeaguilar]

for your example if you want the user to calculate something depending on a selection, regarding my previous post, the variable call would be like this:

$(VariableName( $(=Concat(distinct Product, chr(44) ))

I used this concat function in order to allow users to calculate for example the sum of sales of 1 or any product that is selected in a listbox.

you can also store the $(=Concat(distinct Product, chr(44)) in another variable so it can be easier for end-users to reuse expressions across different variables,

regards

[#6]

Thanks a lot Jaime.

[#7]

Jaime,

I need set that you sed since the setings ->Variables Panel?

best regards.

[jaimeaguilar]

Yes, the easiest way of creating variables is going to settings > variable overview (Panel de variables)

regards

[#9]

ok,

but a mean the sentence of your example '$(Variablename($=Concat(Distinct  Product,chr(44)))'

I can set in the setings or directly in a Expression?

best regards.

[jaimeaguilar]

For this example the expression has to be:

sum({$<Product={'$1'}>}Sales)

So let's say this expression is inside a variable called v1

then when you call it in a chart you have to use this syntax:

$(v1( $(=Concat(Distinct  Product,chr(44))) )) The text in bold is the parameter of your variable.

the $(=Concat(Distinct  Product,chr(44))) can be anything. When the variable is calculated the '$1' in your original expression will be substituted with whatever you put inside the parameter of the variable.