egghelp/eggheads community

Problem with decreasing a variable

2006-06-27T03:35:27-04:00

its equivalent with 'incr i -[lindex $line 0]', however only the expr one will work on negative values.

Statistics: Posted by De Kus — Tue Jun 27, 2006 3:35 am

Problem with decreasing a variable

2006-06-26T17:59:46-04:00

Doenst

Code:

set i [expr {$i - [lindex $line 0]}]

work?

Statistics: Posted by phab — Mon Jun 26, 2006 5:59 pm

Problem with decreasing a variable

2006-06-25T09:43:36-04:00

Code:

[lindex $line 0]

is "2"

Code:

incr i -[lindex $line 0]

means that it is increased by -2, which means it is decreased by 2
obviously you didn't bother to try it[/code]

Statistics: Posted by DragnLord — Sun Jun 25, 2006 9:43 am

Problem with decreasing a variable

2006-06-25T09:09:07-04:00

Yes, it works Sir_Fz. But if i is 3 and it should be decreased the result is 2. With your script it is not 2, but -2. With "trimleft" I can make the variable i positive again, but maybe this is too circumstantial and there is an easier way.

Statistics: Posted by darton — Sun Jun 25, 2006 9:09 am

Problem with decreasing a variable

2006-06-25T07:40:25-04:00

Code:

incr i -[lindex $line 0]

this will decrement i by '[lindex $line 0]' instead of increment.

Statistics: Posted by Sir_Fz — Sun Jun 25, 2006 7:40 am

Problem with decreasing a variable

2006-06-25T06:15:29-04:00

With the '[lindex $line 0]' it is defined what should be increased. So none of your scripts work.

Statistics: Posted by darton — Sun Jun 25, 2006 6:15 am

Problem with decreasing a variable

2006-06-24T23:15:40-04:00

simply:

Code:

incr i -1

in the script you have '[lindex $line 0]' is used to obtain the increment value

Statistics: Posted by DragnLord — Sat Jun 24, 2006 11:15 pm

Re: Problem with decreasing a variable

2006-06-24T21:17:19-04:00

Code:

incr i [lindex $line 0] -1

you do something like "1 +1 -1" but incr allows only one operation like "1+1" or "1-1"

(($i + $y) - $z) it would be something like

Code:

set i [expr [incr i [lindex $line 0]] -1]

Statistics: Posted by Garp — Sat Jun 24, 2006 9:17 pm

Problem with decreasing a variable

2006-06-24T17:45:37-04:00

Hello!
In one of my scripts there is this line:

Code:

incr i [lindex $line 0]

But now I don't want to increase it but I want to decrease it. So I changed it to this:

Code:

incr i [lindex $line 0] -1

It does not work. The error is: Tcl error [flag]: wrong # args: should be "incr varName ?increment?"
What's wrong?

Statistics: Posted by darton — Sat Jun 24, 2006 5:45 pm