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[akordykiewicz@researchcloud.pl]

Hi,
please help me solve my javascript problem. I'm not a specialist and I can't handle it.

I have in PDF form ex. four number fields. A, B, C, D.
Field A is the entrance. Fields B and C do calculations (ex. A+B+C). Field D=A+B+C this is the result.
Now I want to make an auxiliary field D1.
Script operation. After entering the D1 value, the script substitutes the A value, checks the calculations and the D result, and works until the D = D1 condition is met
Thank you for any tips.

Edit
I came to this solution, but the result is always 1 too big

for (var i=1;this.getField("D1").value!=this.getField("D").value;i++){
this.getField("D").value=this.getField("A").value+this.getField("B").value+this.getField("C").value
this.getField("A").value=this.getField("A").value+1
};

[try67]

Change the first line to :

while (this.getField("D1").value!=this.getField("D").value) {

[akordykiewicz@researchcloud.pl]

try67 Thank you, it works. I still have a problem with decimal numbers. At the moment I increase by 1 how to do it so that there are e.g. values of 3.56?

Edit:

I came to the solution (in bold) and it works for the result e.g. 3.50 but it does not work for the result e.g. 3.56 or 3.55

while (getField("D1").value!=this.getField("D").value){
this.getField("A").value=this.getField("A").value+=.1
this.getField("D").value=this.getField("A").value+this.getField("B").value+this.getField("C").value
};

[try67]

Add 0.01 instead of 0.1... There must be a better way to solve this issue then by brute-force, though.

[akordykiewicz@researchcloud.pl]

Thank you for the answer, but it doesn't work.The form hangs.

Unfortunately, I have no other idea. I am not advanced in javascript

[try67]

I'm not surprised. What you're doing is a classic recipe for getting an infinite loop.

What if the value is smaller, not bigger? The while-condition will never be false.

It's not a question of JS knowledge, but a question of math and logic. What exactly are you trying to achieve with this?

[akordykiewicz@researchcloud.pl]

I'm trying to do something that will work like a Goal Seek in Excel.

I know what you are writing but at the beginning I try to find a solution to the basic problem, e.g. only for rising values.

[Thom Parker]

What you've shown above finds the value of A needed to satisfy D = D1.  What's the point? This value is simply 

Given:

D = A + B + C

D1 = A1 + B + C

Difference:

D - D1 = A - A1

Result:

A1 = A - (D - D1)

Why the iteration?

[akordykiewicz@researchcloud.pl]

Thank you Thom. However, my task is a bit more complicated. I tried to present them based on several variables, but it's probably not a good idea and I am misleading you. Thank you for your help and I am closing the topic on my part.