topic Re: String from index position in Python Questions

String from index position

NoahHuntington — Mon, 03 Mar 2014 20:18:29 GMT

Trying to calculate field using all the leftmost characters of [TEXTSTRING] up to the first occurrence of "out" in [TEXTSTRING] whose position has been calculated and placed in [POSITION] field. The following is vbscript but I'm sure there is an easy python solution to this. The script should help clarify...

[position] = first occurrence of "out" in [TEXTSTRING]

label:

Left( [TEXTSTRING], Len( [TEXTSTRING] ) [position] )

I hope this make sense?

Re: String from index position

MathewCoyle — Mon, 03 Mar 2014 20:35:19 GMT

If using field calculator try this.

!TEXTSTRING![:int(!position!)]

int() may or may not be required depending on field type of "position"

Re: String from index position

Anonymous User — Sat, 11 Dec 2021 21:55:14 GMT

Do you mean splitting it up by white space and finding where the word 'out' is within a string? If so, you could get the position with something like this:

>>> a = 'this is out at pos 2'
>>> b = 'out at pos 0'
>>> c = 'pos 3 is out'
>>> def findIndex(string, word):
 return string.split().index(word)

>>> for test in [a, b, c]:
 print findIndex(test, 'out')

 
2
0
3

I don't know much VB so I'm not sure what you're doing once you have the index?

EDIT: Matt's answer is waaaay better than mine.

Re: String from index position

NoahHuntington — Mon, 03 Mar 2014 20:41:19 GMT

If using field calculator try this.
!TEXTSTRING![:int(!position!)]
int() may or may not be required depending on field type of "position"

I have tried both of the following?

!TEXTSTRING![: !postion!]

!TEXTSTRING![: int(!postion!)]

Re: String from index position

Anonymous User — Sat, 11 Dec 2021 21:55:17 GMT

If you are just looking to get everything before the word "out" in a text string, how about:

!TEXTSTRING!.split("out")[0].strip()

Re: String from index position

NoahHuntington — Sat, 11 Dec 2021 21:55:19 GMT

Do you mean splitting it up by white space and finding where the word 'out' is within a string? If so, you could get the position with something like this:
>>> a = 'this is out at pos 2'
>>> b = 'out at pos 0'
>>> c = 'pos 3 is out'
>>> def findIndex(string, word):
 return string.split().index(word)

>>> for test in [a, b, c]:
 print findIndex(test, 'out')

 
2
0
3
I don't know much VB so I'm not sure what you're doing once you have the index?

EDIT: Matt's answer is waaaay better than mine.

No problem. Yeah I'm not sure what your testing in this one? Thanks for chiming in Caleb!

Re: String from index position

NoahHuntington — Sat, 11 Dec 2021 21:55:22 GMT

If you are just looking to get everything before the word "out" in a text string, how about:
!TEXTSTRING!.split("out")[0].strip()

No luck here?

Re: String from index position

MathewCoyle — Mon, 03 Mar 2014 20:57:32 GMT

Could you post a sample of your table you are trying to calculate and the applicable field types?

Re: String from index position

NoahHuntington — Mon, 03 Mar 2014 21:05:10 GMT

Could you post a sample of your table you are trying to calculate and the applicable field types?

Hi Matt

See attached:

label using textstring only...

label does not all show in table fyi.

Re: String from index position

MathewCoyle — Mon, 03 Mar 2014 21:30:50 GMT

Are you trying to calculate a field or create a label?

Re: String from index position

NoahHuntington — Tue, 04 Mar 2014 12:35:08 GMT

Are you trying to calculate a field or create a label?

Ultimately label. In doing so was attempting to create new label field? Open to label expression too!

Re: String from index position

MathewCoyle — Tue, 04 Mar 2014 13:11:57 GMT

If neither of the posted samples worked for you something odd is going on with your data or how you are executing the calculator. Are you sure you are enabling Python instead of VB? What errors or messages do you get?

Re: String from index position

NoahHuntington — Tue, 04 Mar 2014 13:18:46 GMT

Matt,

position is a long, new label field and textstring are string fields...

using:
!TEXTSTRING![:int( !position!)]

received:
error 000539: exceptions.TypeError: cannot concatenate 'str' and 'int' objects.

Re: String from index position

MathewCoyle — Tue, 04 Mar 2014 14:49:08 GMT

Is that your entire expression? Can you take a screenshot of your field calculator window with the code you execute that returns that error? Also can you post the entire error message? And what version of ArcGIS are you using? Something isn't adding up here.

Re: String from index position

NoahHuntington — Tue, 04 Mar 2014 17:18:26 GMT

[ATTACH=CONFIG]31928[/ATTACH]

This is what I'm attempting?

Re: String from index position

MathewCoyle — Sat, 11 Dec 2021 21:55:30 GMT

ERROR 000539: SyntaxError: EOL while scanning string literal (<expression>, line 1)

That is an error with the expression format itself. Double check your field names and that you are using Python instead of VB.

Re: String from index position

NoahHuntington — Wed, 05 Mar 2014 12:59:06 GMT

That is an error with the expression format itself. Double check your field names and that you are using Python instead of VB.

If I ran yesterday according to the picture provided at 11:18 where do you suppose I went wrong? FYI: [postion] although misspelled is the actual field name...

Re: String from index position

MathewCoyle — Sat, 11 Dec 2021 21:55:25 GMT

Can you post the full error you are receiving so we can see what has been passed that causes the error? It should look something like this.

Executing: CalculateField blocks TEST_LABEL "!SOURCEID![:  !TEXT_INTS! ]" PYTHON_9.3 #
Start Time: Tue Mar 04 12:48:53 2014
ERROR 000539: Error running expression: u"FA07908426251"[:  u"2014" ] 
Traceback (most recent call last):
  File "<expression>", line 1, in <module>
TypeError: slice indices must be integers or None or have an __index__ method

Failed to execute (CalculateField).
Failed at Tue Mar 04 12:48:53 2014 (Elapsed Time: 0.04 seconds)

You can find it under the 'Results' tab

Re: String from index position

NoahHuntington — Sat, 11 Dec 2021 21:55:28 GMT

Can you post the full error you are receiving so we can see what has been passed that causes the error? It should look something like this.

Executing: CalculateField blocks TEST_LABEL "!SOURCEID![:  !TEXT_INTS! ]" PYTHON_9.3 #
Start Time: Tue Mar 04 12:48:53 2014
ERROR 000539: Error running expression: u"FA07908426251"[:  u"2014" ] 
Traceback (most recent call last):
  File "<expression>", line 1, in <module>
TypeError: slice indices must be integers or None or have an __index__ method

Failed to execute (CalculateField).
Failed at Tue Mar 04 12:48:53 2014 (Elapsed Time: 0.04 seconds)

You can find it under the 'Results' tab

Messages
Executing: CalculateField OWNERSHIP_TEXT Label "!TEXTSTRING![:int (!postion!)]" PYTHON_9.3 #
Start Time: Tue Mar 04 16:55:32 2014
ERROR 000539: SyntaxError: EOL while scanning string literal (<expression>, line 1)
Failed to execute (CalculateField).
Failed at Tue Mar 04 16:55:32 2014 (Elapsed Time: 0.10 seconds)