trimleft on a numeric field

[Mary Bodoh-Stone]

Hi,

I am new to tcl.  What I am trying to do I figure should be fairly simple but I can’t figure it out….. I need the very first numeric digit in a field.  Am trying trimleft but it’s not working.  Whatever the digit is 1-9, I need it.  Field could be 3-4 digits, but I need the first one.Thanks.

– Mary

Topic

[Jim Kosloskey]

Mary,

string trimleft is for removing characters.

If you want a certain single character then either

string index where index of 0 is character one

or

string range where first and last are indexes to the character(s) you want (like for the first character would be 0 0).

email: jim.kosloskey@jim-kosloskey.com 29+ years Cloverleaf, 59 years IT - old fart.

[Mary Bodoh-Stone]

Hi Jim,

 I tried this… no error but it’s not working either; thanks alot.

set xlateOutVals [ list [ string range [ lindex $xlateInVals 0 ] 0 0 ] ]

or

set xlateOutVals [ string range [ lindex $xlateInVals 0 ] 0 0 ]

Neither works; thanks.

[Jim Kosloskey]

Mary,

Are you sure your lindex of xlateInVals is returning what you want?

email: jim.kosloskey@jim-kosloskey.com 29+ years Cloverleaf, 59 years IT - old fart.

[Mary Bodoh-Stone]

No…my input side is a value of 401 and my output value is the same.  I am expecting/wanting a 4.

[David Barr]

Code:

regexp {^0*([1-9])} [lindex $xlateInVals 0] -> digit
set xlateOutVals [list $digit]

[David Barr]

Actually it wasn’t clear what you want trimmed off the left side of the number. I assumed that it was zeros, but if you change the pattern to {^[^1-9]*([1-9])} it would trim anything except 1-9.

[Mary Bodoh-Stone]

David,

I actually want the very first digit only.

[Mary Bodoh-Stone]

I’m reading this and maybe I still haven’t made it clear.  For example, I have a value of 401 and I want to keep the 4; or 542 and I want to keep the 5.  Thanks.

[Paul Bishop]

try:

set new_field [csubstr $orig_field 0 1]

or

set new_field [string range $orig_field 0 0]

either of these will grab the first character of your input field.

Paul Bishop
Carle Foundation Hospital
Urbana, IL

[Mary Bodoh-Stone]

Thank you everyone; I have it working now.

[Robert Kersemakers]

I am wondering though: can your inbound value also be ‘Hello123’? You would get ‘H’ in return with the last solution. Or do you need the ‘1’ to be returned in this case?

Zuyderland Medisch Centrum; Heerlen/Sittard; The Netherlands

[David Barr]

I think it’s a terminology problem. In TCL, “trim” means to throw away or ignore characters at the beginning or end of a string. I think she just wants to return the first character of a string.

[Max Drown (Infor)]

The c-commands are legacy tcl commands. The better approach moving forward would be like this …

set xlateOutVals

0 1]]

Also, it is important to always treat xlateInVals and xlateOutVals as tcl list objects (and not string objects). Even when you are 100% sure that you inbound value will not contain a space, someone someday may clone your code and use it for values containing spaces.

-- Max Drown (Infor)

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