How do I write a calculation?

[PHP2005]

How do I write a calculation?

I am new on write calculation.

I have a database where I keep record of the registration and workshop,

The registration fields are F1, F2, and F3 and the workshop fields are

W1, W2, W3, and W4

How do I write a calculation

If I am register to any of (F1, F2, or F3) and NONE of the W1, W2, W3, or W4

I would check the radio button as “Registration Only”

If I a register to any of (F1, F2, or F3) and any of W1, W2, W3, or W4

I would check the radio button as “Registration and workshop

If I am not register and only attend any of the workshop

I would check the radio button as “Workshop Only”

Any help will be appreciated!

[dreamingmind]

php2005,

Well there are a lot of ways to do this. How 'bout a Let statement because it will allow us to break this into smaller chunks and make it a little easier to understand.

Let ( [

reg = case( (F1 & F2 & F3) = "" ; 0 ; 1 );

wks = case( (W1 & W2 & W3 & W4) = "" ; 0 ; 2 )

] ;

choose( reg + wks ; "None"; "Registration Only";"Workshop Only";"Registration and Workshop")

)

In a nutshell, I concatenate the two sets of fields and check to see if they have any value. Based on the result, I set a variable to a number so can later add the variables and come up with a unique sum for each possible which I can then use to pick the text I want using a choose function.

Regards, Don

[PHP2005]

Hi Don,

Thank you for your help.

I have the following calculation:

Case ( not IsEmpty (Registration) and IsEmpty ( Workshop ); "Conference Only")&

Case ( not IsEmpty (Registration) and not IsEmpty (Workshop); "Conference and Workshop")&

Case ( IsEmpty (Registration) and not IsEmpty (Workshop); "Workshop Only")&

And my problem now is how do I add a case statement if in case the value of Registration be equal to “Pre-Conference” and not IsEmpty(Workshop); “Pre-Conference Only”)

it will show up Pre-Conference only at the field.

Thank you.

[Anuviel]

I think that Case evaluates until it encounters the first condition only so "and" statement does not make much sense in it - I learned that here on the forums so an If statement would be much better in this case OR I got it wrong.

I might be wrong, get a second opinion before taking any of my advice.

If ( not IsEmpty (Registration) and IsEmpty ( Workshop ); "Conference Only" ; "")

[Genx]

Anuviel - you're right in terms of the case only evaluating until it matches a condition but maybe not in the way you think:

Case( Condition1 ; Result1 ;

Condition2 ; Result2 ;

ConditionN ; ResultN ;

Default If No Conditions Met )

If condition1 is met, then the case function short circuits and throws out Result1 - Condtions2 to n aren't checked because Condition1 evaluated to true.

Conditions can be anything however - the primary thing that is evaluated is whether the expression produces a true or false result:

IsEmpty("") and IsEmpty("") would for example produce true and so Result1 would be thrown out.

The If statement can really be replaced by a single case statement if you really wanted, though it may become less clear:

Case( condition ; true ; false )

If( condition ; true ; false )

PHP 2005 - A case statement evaluates multiple conditions, not one set at a time, so you're statement could be written as:

Case ( IsEmpty (Registration & Workshop); "" ;

IsEmpty ( Workshop ) ; "Conference Only";

IsEmpty (Registration); "Workshop Only";

"Conference and Workshop")

Don - the function's great, but don't use = "" to try and work out if a string is empty:

Let ( [

reg = case( IsEmpty(F1 & F2 & F3) ; 0 ; 1 );

wks = case( IsEmpty(W1 & W2 & W3 & W4) ; 0 ; 2 )

] ;

choose( reg + wks ; "None"; "Registration Only";"Workshop Only";"Registration and Workshop")

)

End random reply :

Edited September 15, 2007 by Guest