a file and basic maths

Im in the middle of writing a program. Part of that prog is to open a .txt file . The format of the file is two colums of numbers seperated by a comma i.e. row one would look like 0.23657, -3.6548,

approximately 3000 rows will be in the file.

I need to read in the data from the file, perform some maths and output the result.

Something like get the average of column 1 and the average from column 2 and add these results together.

Any ideas or source code?

Many thanx, Paul...

I would use a 2 dimensional array, and a principal like pixels.
Eg:

VB Code:

Dim tTable(1, 2999) As String 'might take a while to load
              'X   'Y
Dim inptLine As String 'the input
Open "C:\test.txt" For Input As #1
Do While Not EOF(1)
    Input #1, inptLine
    For i = 0 To 2999
        For j = 0 To 1
            tTable(j, i) = inptLine
        Next j
    Next i
Loop
Close #1

Then you could use something like:

VB Code:

Dim avg As Double
For i = 0 To 2999
    avg = avg + tTable(0, i)
Next i
avg = (avg / 2999)

Unfortunately, if you are using text files, there won't be a quick way for this..

Phreak

You can split the lines with Output = Split(Input, Delimiter).
Output will be an array.

IIRC, when converting strings to numbers VB uses "," as the decimal separator.
You can replace the "." with Output = Replace(Input, ToReplace, ReplaceWith).

But why split?

Visual Basic automatically delimits by commas, and since thats how the file is layed out, 1 input statement would input everything up to either a new line character, or a comma (,).

Phreak

Im gonna try The "phreak" code.
Just one thing..... tTable is just like a 2d array, yes?

Quote:

---

Originally Posted by jeroen79

IIRC, when converting strings to numbers VB uses "," as the decimal separator.
You can replace the "." with Output = Replace(Input, ToReplace, ReplaceWith).

---

When converting strings to numbers, VB will use the seperator that is defined in your regional settings.

i just realised that the above code wont work the way i want it to.

i need to have both the variables in the row to be read in together. i.e. i need to have the x and y values of row one etc at the same time. (part of my formula needs to ultiply the x and y value of a row together. then acculmulate them.) (i know how to do the maths...i just need the two variables read together)
i know i can do this with ttable but it will require at least another loop. id like to do the calculations as the data is being read, in the same loop.

You could do two Inputs each time it goes through the loop and send the result of each Inout to a different variable.

so how do i do that?
(and bty the number of rows will be approx 3000 but the exact number in the file will be unknown)

ok all i got it sorted...... heres the portion of code im using to do that....its a bit messy but its does the job nicely..... (i added in a few RTB's for trouble shooting)
ill be adding in my maths later.
it also is much quicker than i thought. reads in 6000 values via 2 loops and displays them in 2 seconds on a p3.

VB Code:

Private Sub Command3_Click()
 Open "C:\Documents and Settings\paul.cullen\Desktop\log.txt" For Input As #1
 
 
    While Not EOF(1)
 
        Line Input #1, temp$               'read in one line at a time, and put in temp$
        alltext$ = alltext$ & temp$ & (Chr(13)) 'append to alltext$ with line feed. (just for trouble shooting)
 
    
        For I = 1 To Len(temp$) - 1 'the minus one is so that the loop will not read the second comma in the file and repeat for no reason.
                                     
            y = Mid(temp$, I, 1)       'checking for comma
            'n = n + 1                  'acculuminating number of characters before comma is reached
            If y = "," Then             'check for commas
               x$ = Left(temp$, I - 1)  ' at the first comma, this copies all the characters from the left to x$
               allx = allx & x$ & (Chr(13)) '(just for trouble shooting)
               ys$ = Right(temp$, Len(temp$) - I) ' taking all the characters to the right of the comma
               ys$ = Left(ys$, Len(temp$) - I - 1) ' removeing the comma at the end of the "y" data
               ally = ally & ys$ & (Chr(13)) '(just for trouble shooting)
            End If
            
        Next
    Wend
    RichTextBox1 = alltext$ 'temp read viewer. all RTB'sare for troubleshooting purposes.....removes them as needed.
    RichTextBox2 = ally       
    RichTextBox3 = allx
 
Close #1
End Sub

How about:

VB Code:

Input #1, A
  Input #1, B
  DoStuff (A, B)

And if want to split a Line Input result on the comma then Split() would be easier.

looks nice (and way easier)but iv it done my way now. i had to do this for a couple of files so im not gonna change it now but thanks for the help anyway. im sure ill use it in future programming.