Fast way to truncate string
 

Suppose I have the following string.

Dim s as String
s = "Always eat lots of fruits and vegetables every day."

I would like to be able to truncate this string as quickly
as possible, beginning from a word of my choosing, all
the way to the end of the string.

So, if I choose the word "and" as my target word, the
above string should be transformed into:

"Always eat lots of fruits "

Essentially, all text after the first occurence of "and"
was removed from the string.

I'm looking for solution that runs quickly. Thanks!

~Rob

Fast way to truncate string
 

Suppose I have the following string.

Dim s as String
s = "Always eat lots of fruits and vegetables every day."

I would like to be able to truncate this string as quickly
as possible, beginning from a word of my choosing, all
the way to the end of the string.

So, if I choose the word "and" as my target word, the
above string should be transformed into:

"Always eat lots of fruits "

Essentially, all text after the first occurence of "and"
was removed from the string.

I'm looking for solution that runs quickly. Thanks!

~Rob

Try...

s = Mid(s, 1, InStr(s, "and") - 1)

OR

s = TruncateString(s, "and")

Function TruncateString(sText, sFind)
TruncateString = Mid(sText, 1, InStr(sText, sFind) - 1)
End Function

--
Garry

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Fast way to truncate string
 

Better function...

Function TruncateString(sText, sFind, Optional lStart& = 1)
TruncateString = Mid(sText, lStart, InStr(sText, sFind) - lStart)
End Function

...where you can specify the start point as well as the end point...

s = TruncateString(s, "and", InStr(s, "eat"))

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Fast way to truncate string
 

Il giorno venerdì 27 marzo 2015 13:03:47 UTC+1, Robert Crandal ha scritto:
Suppose I have the following string.
Dim s as String
s = "Always eat lots of fruits and vegetables every day."
I would like to be able to truncate this string as quickly
as possible, beginning from a word of my choosing, all
the way to the end of the string.
So, if I choose the word "and" as my target word, the
above string should be transformed into:
"Always eat lots of fruits "
Essentially, all text after the first occurence of "and"
was removed from the string.
I'm looking for solution that runs quickly. Thanks!

Hi,
Try

Left$(k, InStr(1, k, f, vbTextCompare) - 1)
--
Ciao! :)
Maurizio

Fast way to truncate string
 

Il giorno venerdì 27 marzo 2015 13:03:47 UTC+1, Robert Crandal ha
scritto:
Suppose I have the following string.
Dim s as String
s = "Always eat lots of fruits and vegetables every day."
I would like to be able to truncate this string as quickly
as possible, beginning from a word of my choosing, all
the way to the end of the string.
So, if I choose the word "and" as my target word, the
above string should be transformed into:
"Always eat lots of fruits "
Essentially, all text after the first occurence of "and"
was removed from the string.
I'm looking for solution that runs quickly. Thanks!

Hi,
Try

Left$(k, InStr(1, k, f, vbTextCompare) - 1)

Given the OP's criteria is "..as quickly as possible,...", the Mid()
function is considerably faster!

--
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Fast way to truncate string
 

Il giorno venerdì 27 marzo 2015 15:24:55 UTC+1, GS ha scritto:
Il giorno venerdì 27 marzo 2015 13:03:47 UTC+1, Robert Crandal ha
scritto:
Suppose I have the following string.
Dim s as String
s = "Always eat lots of fruits and vegetables every day."
I would like to be able to truncate this string as quickly
as possible, beginning from a word of my choosing, all
the way to the end of the string.
So, if I choose the word "and" as my target word, the
above string should be transformed into:
"Always eat lots of fruits "
Essentially, all text after the first occurence of "and"
was removed from the string.
I'm looking for solution that runs quickly. Thanks!
Left$(k, InStr(1, k, f, vbTextCompare) - 1)
Given the OP's criteria is "..as quickly as possible,...", the Mid()
function is considerably faster!

' Windows 7/64 - Excel 2013
'
Option Explicit

Private Declare Function GetTickCount Lib "kernel32" () As Long

Private Sub Test()
Const DebugOn = False
Const k = "Always eat lots of fruits and vegetables every day."
Const f = "And"

Dim i As Long
Dim i1 As Long
Dim t As Long
Dim t1 As Long
Dim d As Long

Dim s As String

If DebugOn Then
t = 1
t1 = 1
Else
t = 100000
t1 = 5
End If

For i1 = 1 To t1

If DebugOn Then
Debug.Print "Split:", "'" & Split(k, f, Compa=vbTextCompare)(0) & "'"
Else
d = GetTickCount
For i = 1 To t
s = Split(k, f, Compa=vbTextCompare)(0)
Next
d = GetTickCount - d
Debug.Print Format$(d, "0") '
End If

If DebugOn Then
Debug.Print "Mid$:", "'" & Mid$(k, 1, InStr(1, k, f, vbTextCompare) - 1) & "'"
Else
d = GetTickCount
For i = 1 To t
s = Mid$(k, 1, InStr(1, k, f, vbTextCompare) - 1)
Next
d = GetTickCount - d
Debug.Print Format$(d, "0") '
End If

If DebugOn Then
Debug.Print "Left$:", "'" & Left$(k, InStr(1, k, f, vbTextCompare) - 1) & "'"
Else
d = GetTickCount
For i = 1 To t
s = Left$(k, InStr(1, k, f, vbTextCompare) - 1)
Next
d = GetTickCount - d
Debug.Print Format$(d, "0") '
End If

If DebugOn Then
Debug.Print "Mid:", "'" & Mid(k, 1, InStr(1, k, f, vbTextCompare) - 1) & "'"
Else
d = GetTickCount
For i = 1 To t
s = Mid(k, 1, InStr(1, k, f, vbTextCompare) - 1)
Next
d = GetTickCount - d
Debug.Print Format$(d, "0") '
End If

If DebugOn Then
Debug.Print "Left:", "'" & Left(k, InStr(1, k, f, vbTextCompare) - 1) & "'"
Else
d = GetTickCount
For i = 1 To t
s = Left(k, InStr(1, k, f, vbTextCompare) - 1)
Next
d = GetTickCount - d
Debug.Print Format$(d, "0") '
End If

Debug.Print

Next
End Sub

Split Mid$ Left$ Mid Left
187 109 109 109 110
218 109 94 109 125
203 93 93 110 109
218 94 109 109 125
187 109 109 109 110
187 94 109 109 109
187 109 109 110 109
187 94 109 109 110
187 109 109 109 110
187 110 93 109 110
187 109 94 125 109
187 109 94 124 110
187 109 94 124 110
172 94 109 109 110
187 94 109 109 109
187 93 110 109 109
187 109 94 124 110
187 109 94 109 125
187 110 93 109 110
187 109 94 109 125
Min : 172 93 93 109 109
Max : 218 110 110 125 125
Average : 190,15 103,75 101,40 112,15 112,70
Rank : 5 2 1 3 4
0,0000% -45,4378% -46,6737% -41,0202% -40,7310%

Fast way to truncate string
 

Given the simplicity of your test, this results about 50/50 on my
machine after 5 runs. No surprise!

Generally speaking, though, the Mid() function is considered to be
faster in the VB community forums. Having tested with more complex
uses, I agree with that assessment!

--
Garry

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Fast way to truncate string
 

Il giorno venerdì 27 marzo 2015 18:11:08 UTC+1, GS ha scritto:
Given the simplicity of your test, this results about 50/50 on my
machine after 5 runs. No surprise!
Generally speaking, though, the Mid() function is considered to be
faster in the VB community forums. Having tested with more complex
uses, I agree with that assessment!

Anyway, string functions (Mid$, Left$, ...) are faster then variant.

--
Ciao! :)
Maurizio

Fast way to truncate string
 

Il giorno venerdì 27 marzo 2015 18:11:08 UTC+1, GS ha scritto:
Given the simplicity of your test, this results about 50/50 on my
machine after 5 runs. No surprise!
Generally speaking, though, the Mid() function is considered to be
faster in the VB community forums. Having tested with more complex
uses, I agree with that assessment!

Anyway, string functions (Mid$, Left$, ...) are faster then variant (Mid, Left, ...).

--
Ciao! :)
Maurizio

Fast way to truncate string
 

Il giorno venerdì 27 marzo 2015 18:11:08 UTC+1, GS ha scritto:
Given the simplicity of your test, this results about 50/50 on my
machine after 5 runs. No surprise!
Generally speaking, though, the Mid() function is considered to be
faster in the VB community forums. Having tested with more complex
uses, I agree with that assessment!

Anyway, string functions (Mid$, Left$, ...) are faster then variant
(Mid, Left, ...).

I agree! My bad for not using...

--
Garry

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Fast way to truncate string
 

As Maurizio pointed out.., here's a version optimized for VB[A} use.


Function TruncateString$(sText, sFind, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function

The original version posted was intended for use with VBScript as well
as VB[A}. The 2nd version not for VBScript because lStart was 'typed'!

--
Garry

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Fast way to truncate string
 

"GS" wrote:

As Maurizio pointed out.., here's a version optimized for VB[A} use.


Excellent. I figured the best way would involve using the
Instr() function in conjunction with Mid() or Left() or whatever.

Thanks again Gary and Maurizio

Fast way to truncate string
 

"GS" wrote:

As Maurizio pointed out.., here's a version optimized for VB[A}
use.


Excellent. I figured the best way would involve using the
Instr() function in conjunction with Mid() or Left() or whatever.

Thanks again Gary and Maurizio

I went with Mid$() so you could start anywhere. Just bear in mind the
start position MUST be before the end position!

--
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Fast way to truncate string
 

Added 'type' to the args as well...


Function TruncateString$(sText$, sFind$, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function

--
Garry

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Fast way to truncate string
 

"GS" wrote:

I went with Mid$() so you could start anywhere. Just bear in mind the
start position MUST be before the end position!


Yup, that makes sense. Setting "lStart" equal to 1 by default seems
to be the best way. 8)

Fast way to truncate string
 

"GS" wrote:

Function TruncateString$(sText, sFind, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function


Do you know why I'm getting a "Type mismatch" error with this
code?:

'--------------------
Public Function TruncateString$(sText, sFind, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function
'--------------------
Sub TestTruncate()

Dim i As Integer
Dim sFilename As String

sFilename = "C:\out.txt"
sPhrases = Split("Hello world", "Goodbye world", "Not a good world today")

i = FreeFile()
Open sFilename For Output As #i

Print #i, TruncateString$(sPhrases(0), "world")

Close #i

End Sub

Fast way to truncate string
 

Hi Robert,

Am Sun, 29 Mar 2015 03:03:03 -0700 schrieb Robert Crandal:

sPhrases = Split("Hello world", "Goodbye world", "Not a good world today")

try:
sphrases = Split("Hello world, Goodbye world, Not a good world today", ", ")
or
sphrases = Array("Hello world", "Goodbye world", "Not a good world today")


Regards
Claus B.
--
Vista Ultimate / Windows7
Office 2007 Ultimate / 2010 Professional

Fast way to truncate string
 

Okay, I have a different problem with the TruncateString()
function. I am getting an "Invalid procedure call or argument"
message. Not sure why. Here is the code:
(The error occurs in the main_test() subroutine)

'----------------------------------------------------
Sub main_test()

Dim sFile1 As String
Dim sFile2 As String
Dim n As Integer
Dim i As Integer
Dim j As Integer
Dim vData ' variant

gsBlankLine = Chr(13) & Chr(13) & Chr(10)
sFile1 = "C:\inp.txt"
sFile2 = "C:\out.txt"

'Group directly into chapters divided by "*" borders
vData = Split(ReadTextFile(sFile1), String(80, "*"))

i = FreeFile()

Open sFile2 For Output As #i

' Scan all narratives
For n = LBound(vData) To UBound(vData)

sClean = Split(vData(n), gsBlankLine)
For j = LBound(sClean) To UBound(sClean)

'
' ******** Error occurrs here *********
'
Print #i, TruncateString(sClean(j), "especially so")

Next ' j

Next ' n

Close #i

End Sub
'-------------------------
Public Function ReadTextFile$(Filename$)
' Reads large amounts of data from a text file in one single step.
Dim iNum%
On Error GoTo ErrHandler
iNum = FreeFile(): Open Filename For Input As #iNum
ReadTextFile = Space$(LOF(iNum))
ReadTextFile = Input(LOF(iNum), iNum)

ErrHandler:
Close #iNum: If Err Then Err.Raise Err.Number, , Err.Description
End Function 'ReadTextFile()
'----------------------------
Public Function TruncateString$(sText, sFind, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function

Fast way to truncate string
 

Hi Robert,

Am Tue, 31 Mar 2015 01:54:51 -0700 schrieb Robert Crandal:

Sub main_test()

Dim sFile1 As String
Dim sFile2 As String
Dim n As Integer
Dim i As Integer
Dim j As Integer
Dim vData ' variant

gsBlankLine = Chr(13) & Chr(13) & Chr(10)
sFile1 = "C:\inp.txt"
sFile2 = "C:\out.txt"

'Group directly into chapters divided by "*" borders
vData = Split(ReadTextFile(sFile1), String(80, "*"))

i = FreeFile()

Open sFile2 For Output As #i

' Scan all narratives
For n = LBound(vData) To UBound(vData)

sClean = Split(vData(n), gsBlankLine)
For j = LBound(sClean) To UBound(sClean)

'
' ******** Error occurrs here *********
'
Print #i, TruncateString(sClean(j), "especially so")

Next ' j

Next ' n

Close #i

End Sub

drag vData and sClean into the watch window and step with F8 through
your code.
What about the borders? Are there 20 asterix as in the question before?
Then try:
strSplit = Application.Rept("*", 20)
vData = Split(ReadTextFile(sFile1), String(80,strSplit))


Regards
Claus B.
--
Vista Ultimate / Windows7
Office 2007 Ultimate / 2010 Professional

Fast way to truncate string
 

What about the borders? Are there 20 asterix as in the question
before?
Then try:
strSplit = Application.Rept("*", 20)
vData = Split(ReadTextFile(sFile1), String(80,strSplit))

This suggests each paragraph is delimited by 1600 asterisks! If 20
asterisks like before then...

vData = Split(ReadTextFile(sFile1), String(20, "*"))

--
Garry

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Fast way to truncate string
 

Try using this optimized version I posted earlier...

Function TruncateString$(sText$, sFind$, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function

--
Garry

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Fast way to truncate string
 

"GS" wrote:
Try using this optimized version I posted earlier...

Function TruncateString$(sText$, sFind$, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function


This function causes the following error:

Compile error:
ByRef argument type mismatch

Seems like the problem is related to the data being passed
into the "sText$" parameter, but I'm not sure.

Fast way to truncate string
 

"Claus Busch" wrote:

drag vData and sClean into the watch window and step with F8 through
your code.
What about the borders? Are there 20 asterix as in the question before?
Then try:
strSplit = Application.Rept("*", 20)
vData = Split(ReadTextFile(sFile1), String(80,strSplit))


I have been testing different border sizes, such as 20 and 80. I
didn't think this would affect the code because the Split() function
discards the borders and only stores each inner string into an
array.

The main data types being used in my code are variant, array, and
string. It seems there is a problem with the data types being passed into
the TruncateString() function, but I'm not sure.

Fast way to truncate string
 

"GS" wrote:
Try using this optimized version I posted earlier...

Function TruncateString$(sText$, sFind$, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function


This function causes the following error:

Compile error:
ByRef argument type mismatch

Seems like the problem is related to the data being passed
into the "sText$" parameter, but I'm not sure.

Data type was changed from Variant in the original version to String as
last posted (shown here)...

Sub Truncate()
Const s$ = "Always eat lots of fruits and vegetables every day."
Const f$ = "and"
Dim sz$, lPos&
lPos = InStr(s, "eat")
sz = TruncateString(s, f, lPos): Debug.Print sz
End Sub

Function TruncateString$(sText$, sFind$, Optional lStart& = 1)
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
End Function

...which returns "eat lots of fruits".

--
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Fast way to truncate string
 

"GS" wrote:

Data type was changed from Variant in the original version to String as
last posted (shown here)...


How do I fix this? Most of the data that I'm working with are strings.
I have tried using different combinations of CStr() or CVar(), and I
even tried changing your function declaration to the following:

Function TruncateString$(sText$ as String, sFind$, '.....)
or
Function TruncateString$(ByVal sText$ as String, sFind$, '.....)

The various errors that I'm getting a
"Invalid procedure call or argument"
"Compile error: ByRef argument type mismatch"

Again, here was the code that I was testing:
'--------------------------------------------------------------------------------
Sub main_test()

Dim sFile1 As String
Dim sFile2 As String
Dim n As Integer
Dim i As Integer
Dim j As Integer
Dim vData ' variant

gsBlankLine = Chr(13) & Chr(13) & Chr(10)
sFile1 = "C:\inp.txt"
sFile2 = "C:\out.txt"

'Group directly into chapters divided by "*" borders
vData = Split(ReadTextFile(sFile1), String(80, "*"))

i = FreeFile()
Open sFile2 For Output As #i

' Scan all narratives
For n = LBound(vData) To UBound(vData)

sClean = Split(vData(n), gsBlankLine)
For j = LBound(sClean) To UBound(sClean)

'
' ******** Error occurs here *********
'
Print #i, TruncateString(sClean(j), "especially so")

Next ' j

Next ' n
Close #i

End Sub

Fast way to truncate string
 

"GS" wrote:

Data type was changed from Variant in the original version to
String as last posted (shown here)...


How do I fix this? Most of the data that I'm working with are
strings.
I have tried using different combinations of CStr() or CVar(), and I
even tried changing your function declaration to the following:

Function TruncateString$(sText$ as String, sFind$, '.....)
or
Function TruncateString$(ByVal sText$ as String, sFind$, '.....)

The various errors that I'm getting a
"Invalid procedure call or argument"
"Compile error: ByRef argument type mismatch"

I have Lou Gehrig's and so I use data type symbols to save typing...

$ = As String
& = As Long
% = As Integer
# = As Double
! = As Single
@ = As Currency

...and the latest version function works with sample data typed as shown
in the Test_ sub.

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Fast way to truncate string
 

gsBlankLine = Chr(13) & Chr(13) & Chr(10)

Where & how have you declared gsBlankLine?

--
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Fast way to truncate string
 

"GS" wrote:
gsBlankLine = Chr(13) & Chr(13) & Chr(10)

Where & how have you declared gsBlankLine?


It is declared globally as:

Dim gsBlankLine$

Fast way to truncate string
 

"GS" wrote:
gsBlankLine = Chr(13) & Chr(13) & Chr(10)

Where & how have you declared gsBlankLine?


It is declared globally as:

Dim gsBlankLine$

Better that it be...

Public gsBlankLine$

...else it's scope using Dim makes it module level.

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Garry

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Fast way to truncate string
 

"GS" wrote:

Data type was changed from Variant in the original version to
String as last posted (shown here)...


How do I fix this? Most of the data that I'm working with are
strings.
I have tried using different combinations of CStr() or CVar(), and I
even tried changing your function declaration to the following:

Function TruncateString$(sText$ as String, sFind$, '.....)
or
Function TruncateString$(ByVal sText$ as String, sFind$, '.....)

The various errors that I'm getting a
"Invalid procedure call or argument"
"Compile error: ByRef argument type mismatch"

Again, here was the code that I was testing:
'--------------------------------------------------------------------------------
Sub main_test()

Dim sFile1 As String
Dim sFile2 As String
Dim n As Integer
Dim i As Integer
Dim j As Integer
Dim vData ' variant

gsBlankLine = Chr(13) & Chr(13) & Chr(10)
sFile1 = "C:\inp.txt"
sFile2 = "C:\out.txt"

'Group directly into chapters divided by "*" borders
vData = Split(ReadTextFile(sFile1), String(80, "*"))

i = FreeFile()
Open sFile2 For Output As #i

' Scan all narratives
For n = LBound(vData) To UBound(vData)

sClean = Split(vData(n), gsBlankLine)
For j = LBound(sClean) To UBound(sClean)

'
' ******** Error occurs here *********
'
Print #i, TruncateString(sClean(j), "especially so")

Next ' j

Next ' n
Close #i

End Sub

Why are you writing one line at a time? Why not edit the array
elements, then 'dump' its contents into a file in 1 shot???

--
Garry

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Fast way to truncate string
 

I was able to duplicate the exception by using a word that wasn't in
the string being truncated. That precludes that you need to know the
contents of the string being truncated contains the search string...

Function TruncateString$(sText$, sFind$, Optional lStart& = 1)
If InStr(sText, sFind) 0 Then
'Truncate
TruncateString = Mid$(sText, lStart, InStr(sText, sFind) - lStart)
Else
'Return original string
TruncateString = sText
End If
End Function

--
Garry

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