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Posted: **Fri Feb 21, 2014 5:29 am**

Hello,

This is probably a VERY basic question but I just cannot get it working:

I have 2 fields: a and b
field a contains few tab delimited numbers: 002 005 009 and I put it into variable: numbers
field b contains tab delimited rows and columns and I put it into variable: falsetrue

001 false
002 false
003 false
004 false
005 false
006 false
007 false
008 false
009 false
010 false

I want to replace false with true in falsetrue in the lines that have the same numbers as in numbers

using this code:

Code: Select all

local Counter
on mouseUp
   set itemDel to tab
   put fld "a" into numbers
   put fld "b" into falsetrue
   
   repeat for each line i in falsetrue
      if item 1 of i is among the items in numbers then 
         put "true" into item 2 of i
         add 1 to Counter
      end if
   end repeat
   
   put falsetrue into msg box
end mouseUp

Please let me know, where is the fault?

Thanks.

keram

Posted: **Fri Feb 21, 2014 6:26 am**

Well, first off, you must use the keyword "of" instead of "in" when using the "is among" operator. Though these two may often be interchanged, they cannot be here.

Anyway, try this:

Code: Select all

on mouseUp
   set itemDel to tab
   put fld "a" into numbers
   put fld "b" into falsetrue
   
   repeat for each line i in falsetrue
      if item 1 of i is in numbers then 
         put "true" into item 2 of i
         add 1 to Counter
      end if
   end repeat
   
   put falsetrue into msg box
end mouseUp

What does "counter" do?

I have not really gone into this deeply, but the problem was in the "is among the items..." line. I just cut through that with a broader brush. Go back, though, and see if you can figure out where it failed. Write back when you do.

Craig Newman

Posted: **Fri Feb 21, 2014 9:36 am**

Thanks Craig,

It works now with a small addition:
put i & cr after temp

so the code is:

Code: Select all

on mouseUp
   set itemDel to tab
   put fld "a" into numbers
   put fld "b" into falsetrue
   answer falsetrue
   
   repeat for each line i in falsetrue
      if item 1 of i is in numbers then 
         --         if item 1 of i is among items of numbers then -- this works equally well
         put "true" into item 2 of i
      end if
      put i & cr after temp
   end repeat
   put temp into falsetrue
   put falsetrue into msg box
end mouseUp

dunbarx wrote:What does "counter" do?

It's not needed here in this form of the repeat.

So now I have 2 questions that follow this:

1. Suppose that I have 1000 lines in field b and 300 numbers in field a. Is this method, of repeating/looping through each line the fastest one?
What could be other ways?

2. If I have now the new field b with these rows and columns that was put into variable falsetrue:

001 false
002 true
003 false
004 false
005 true
006 false
007 false
008 false
009 true
010 false

and a 3rd field c like this that was put into variable text:

001 false gasfgagag
002 false gsdgjdj
003 false xbxbxvb
004 false xcvbsdhs
005 false ghfjfgj
006 false shhsh
007 false fgjhfhjfgj
008 false sfgsgs
009 false dghsaf
010 false wytufdhj

What is the fastest way of replacing false with true in the lines of text variable that have the same numbers as true numbers in falsetrue?

Of course I could extract the numbers from falsetrue lines that have true and replace false with true in text variable in the same way as above.
But is there some faster, direct way, without that intermediary step?
Maybe merging falsetrue with text in some way and then deleting one of the number columns and the complete false column?
Or any other way?

keram

Posted: **Fri Feb 21, 2014 10:51 am**

OK, I tried with the following:
(had to change the variable text to textlines)

Code: Select all

on mouseUp
   local falsetrue,textlines
   set itemDel to tab
   put fld "b" into falsetrue
   put fld "c" into textlines
   
   repeat  with i=1 to number of lines in textlines
      if item 2 of line i of falsetrue is "true" then
         put "true" into item 2 of line i of textlines
      end if
      put line i of textlines & cr after temp
      add 1 to i
   end repeat
   put temp into textlines
   put textlines into msg box
   
end mouseUp

but it puts this into msg box:

001 false gasfgagag
003 false xbxbxvb
005 true ghfjfgj
007 false fgjhfhjfgj
009 true dghsaf

What's wrong?

keram

Posted: **Fri Feb 21, 2014 3:11 pm**

Keram.

What happens when you step through the handler? You are going to find something, perhaps the counter is not correlating the correct relationship between the number of lines in textlines to the number of lines of falseTrue?

Where is the odd garbled text coming from? It has to exist somewhere in your fields, no?

Craig

Posted: **Fri Feb 21, 2014 5:41 pm**

Hi Craig,

dunbarx wrote: What happens when you step through the handler?

I've never done it before but I assume it means setting Breakpoints at certain lines.
I did at lines 7 - 13 which is the repeat control structure, but it loops just 6 times and then puts the result in the msg box. It should loop 10times right?

dunbarx wrote:Where is the odd garbled text coming from? It has to exist somewhere in your fields, no?

I just typed it in quickly just to have some text in these fields. Yes it exists in field c and variable textlines.
Both fields have the same number of lines...

Still don't know where to correct it.

keram

Posted: **Fri Feb 21, 2014 6:54 pm**

Hi.

Just know that you can place a temporary breakpoint by simply clicking in the line number column. Or you can place a "breakpoint" command in the code itself. The breakpoint should go at the "if" line

If your loop only runs six times, it means that the loop index, loaded via the property you specified (the number of lines in textLines) was initialized at 6, the number of lines in that variable.

Anyway, is the "put line i of textLines..." properly placed? It seems it ought to go inside the "if" structure. Watch absolutely everything when you step through.

The good news is that you will soon figure this out.

Craig

Posted: **Fri Feb 21, 2014 7:52 pm**

In your handler, you're using a counting variable "i", which increments by one at the top of each iteration. Within the repeat loop you also add 1 to i. That increments it again, which is why it is skipping every other line. Delete the "add 1 to i" line and it should work.

This handler will fail if the two lists do not have exactly the same number of lines, which your first post indicated was the case. I'd loop through the smaller set rather than the larger, main set. It will not only be faster, but you'll avoid trying to find nonexistent lines.

You'll get even faster results if you split the sets into arrays with the initial numerical item as keys.

Code: Select all

on mouseUp
  local falsetrue,textlines
  put fld "b" into falsetrue
  split falsetrue by cr and tab
  put fld "c" into textlines
  split textlines by cr and tab
  set the itemDel to tab
  repeat for each line L in keys(falsetrue)
      if item 1 of falsetrue[L] is "true" then
           put "true" into item 1 of textlines[L]
      end if
  end repeat
  combine textlines by cr and tab
  put textlines into msg box
end mouseUp

Posted: **Sat Feb 22, 2014 3:31 am**

Hi Craig,

Thanks for your tips and clarifying how breakpoints work.
Yes, I had to review how counters and repeat structures work.

dunbarx wrote:is the "put line i of textLines..." properly placed?

Yes, it is, since I want to get all the lines - not only the ones with true.

Cheers.

keram

Posted: **Sat Feb 22, 2014 4:01 am**

Hi Jacque,

Thanks a lot for your comments, correcting the mistakes and tips

jacque wrote:This handler will fail if the two lists do not have exactly the same number of lines, which your first post indicated was the case.

Do you mean the very first one at the top? The 2 lists: one with just 3 numbers and the second with 10 lines?
If yes,

jacque wrote:I'd loop through the smaller set rather than the larger, main set.

Then if I loop through the list with these 3 numbers I can only get the result list with only the true ones, but I'd like to get all 10.

But if you mean these ones:
001 false
002 true
003 false
004 false
005 true
006 false
007 false
008 false
009 true
010 false

and
001 false gasfgagag
002 false gsdgjdj
003 false xbxbxvb
004 false xcvbsdhs
005 false ghfjfgj
006 false shhsh
007 false fgjhfhjfgj
008 false sfgsgs
009 false dghsaf
010 false wytufdhj

then they both have the same number of lines...

keram

Posted: **Sat Feb 22, 2014 7:07 am**

You can loop through the shorter set and still get all the lines. Just replace what's in the longer list with the values in the shorter one:

Code: Select all

on mouseUp -- loop through shorter list
  local falsetrue,textlines
  set itemDel to tab
  put fld "b" into falsetrue
  put fld "c" into textlines
  
  repeat  with i=1 to number of lines in falsetrue
      if item 2 of line i of falsetrue is "true" then
           put "true" into item 2 of line (word 1 of line i of falsetrue) of textlines
      end if
  end repeat
  put textlines into msg box   
end mouseUp

The array method is much faster, but this one may be easier to understand.

Posted: **Sat Feb 22, 2014 11:18 am**

Thanks again Jacque,

It's clear now. It's good to learn from examples.
Array method is also quite understandable, I may use it for lager lists.

keram

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