replacing data in existing arrays with new data - dataframe

I want to replace a section of a vector with another vector.
In VBA or FORTRAN it would be done something like this.
Dim v1(10000)
Dim v2(1000)
'something to fill both vectors with floating point numbers'
For n = 1 to 1000 jj = 1000 + n v1(jj) = v2(n) next n
How do I do this in python? Seems like very common engineering stuff to me. Trivial in old languages.
I tried lots of things, including simply overwriting, deleting a section of the larger vector and then appending the smaller one, breaking the larger vector into three pieces then combine: part1 + v2 + part3.
the deleting operations seemed to remove the data but not the original indices

Related

What is the best/fastest method of filling an array with numbers between two values?

I've got a background thread which adds numbers to an array, this call happens often so i'm just curious if there's a faster method of adding the numbers to the array?
I need to add all the numbers between two values (values will be different depending on the situation), example 1 to 4 which would add 1,2,3 & 4.
However, when I make the call, it would be adding much larger arrays similar to 500 to 1000 etc which sometimes takes a little longer depending on how many numbers need to be added.
At the moment i'm using something similiar to this:
Dim ListOfNumbers As New List(Of Integer)
For i = 1 To 100000
If ListOfNumbers.Contains(i) = False Then
ListOfNumbers.Add(i)
End If
Next
Is there any other method that I could use which might be faster?
(Avoiding duplicate values in the array if possible)
I doubt this is driving your program's performance. Moreover, the best option may depend on how you plan to use these numbers, where you may find you actually can noticeably improve performance by using something like IEnumerable throughout your code, rather than an array.
With that in mind, I suggest this option:
int start = 1; int stop = 100000;
var list = Enumerable.Range(start, stop - start).ToArray()
Such that you can easily remove the ToArray() later if desired.
As for the existing code... You control both the List and the loop. Checking .Contains()is not necessary, and probably taking up a significant part of the execution time here. Just remove that check. You can also optimize some by pre-setting the size of the list:
Dim size As Integer = 100000
Dim ListOfNumbers As New List(Of Integer)(size)
For i = 1 To size
ListOfNumbers.Add(i)
Next

Word Macro for separating a comma-separated list to columns

I have a very large set of data that represents cartesian coordinates in the form x0,y0,z0,x1,y1,z1...xn,yn,zn. I need to create a new line at the end of each xyz coordinate. I have been trying to record a macro that moves a certain number of spaces from the beginning of each line, then creates a new line. This, of course, will not work since the number of digits in each xyz coordinate differs.
How can I create a macro to do this in Microsoft Word?
Try this:
Public Sub test()
Dim s As String
Dim v As Variant
Dim t As String
Dim I As Long
s = "x0,y0,z0,x1,y1,z1,xn,yn,zn"
v = Split(s, ",")
t = ""
For I = LBound(v) To UBound(v)
t = t + v(I)
If I Mod 3 = 2 Then
t = t + vbCr
Else
t = t + ","
End If
Next I
t = Left(t, Len(t) - 1)
Debug.Print t
End Sub
The Split function splits a string along the delimiter you specify (comma in your case), returning the results in a 0-based array. Then in the For loop we stitch the pieces back together, using a carriage return (vbCR) every third element and a comma otherwise.
The final (optional) step is to remove the trailing carriage return.
Hope that helps
The question placed before us was most clearly asked
“Please produce a macro sufficient to the task
I have Cartesian coordinates, a single line of these
Array them in many lines, triplets if you please!”
Instinctively we start to code, a solution for this quest
Often without asking, “Is this way truly best?”
But then another scheme arises from the mind
That most venerated duo: Word Replace and Find
Provide the two textboxes each an encantation
Check the Wildcard option and prepare for Amazation!
Forgive me!
In Word open Find/Replace
Click the More button and check the Use wildcards box
For Find what enter ([!,]{1,},[!,]{1,},[!,]{1,}),
For Replace with enter \1^p
Use Find Next, Replace and Replace All as usual
How it works
With wildcards, [!,]{1,} finds one or more chars that are NOT commas. This idiom is repeated 3 times with 2 commas separating the 3 instances. This will match 3 comma-delimited coordinates. The whole expression is then wrapped in parentheses to created an auto-numbered group (in this case Group #1). Creating a group allows us to save text that matches the pattern and use it in the Replace box. Outside of the parentheses is one more comma, which separates one triplet of coordinates from the next.
In the Replace box \1 retrieves auto-numbered group 1, which is our coordinate triplet. Following that is ^p which is a new paragraph in Word.
Hope that helps!

Change the color for each line

I got a console application that draws line in a 3D CAD program. Now to make this more clear i want to change these lines in different colors.
My code read variables from a text-file and calculates data from it and then makes a lines from this calculated data.
This process gets repeated with every line in the text file wich contains data.
Now i want visual basic to change the color everytinme a new line is drawn, so i get different colored lines.
I tried using a For.. To.. Step method, but this didnt work. I also tried to use the variables from my text file( these are different so when a new line got read the RGB code will change) but this will geve me only a lot of blue colors.
Any suggestions?
EDit:
This is what i use to draw the curves, the RGB code has to cahnge everytime when a line with new data is made:
' Creating a Curve2d object by using the above defined points
objLineString = objLineStrings.AddByPoints(PointCount:=points, points:=dataArray)
objGeometricStyle = objLineString.Style
color = objGeometricStyle.LinearColor
objGeometricStyle.LinearColor = RGB(0,0,0)
What about :
Dim rand As New Random() ' Used to generate random numbers
Dim colors(100) as Integer
' Create the colors
For i as Integer = 0 to 100 Step 1
colors(i) = RGB(rand.Next(256), rand.Next(256), rand.Next(256))
Next
For i As Integer = 0 To 100 Step 1 ' Adjust to your needs
' Creating a Curve2d object by using the above defined points
objLineString = objLineStrings.AddByPoints(PointCount:=points, points:=dataArray)
objGeometricStyle = objLineString.Style
color = objGeometricStyle.LinearColor
objGeometricStyle.LinearColor = colors(i Mod 100) ' Mod returns the remainder of i / 100, so it's always less than 100.
Next
This won't always give you "pretty" colors, but they'll be different for each line. If you want control over the generated colors, you could set up an array of predefined colors and use these in your iteration.

pass 1d array of length > 2^16 to an excel column with vb.net

If I have a 1 dimensional array of 1 million indexes, is there a way to do a one-liner to pass the array into a sheet?
This works for arr.length < 2^16
wk.Range(String.Concat("a1:a", arr.Length)).Value = XlApp.Application.transpose(arr)
but not for arr.length = 1 million. I've done this in VBA, but it takes several lines of code and isn't very efficient.
I've also seen a one-liner done in Python, so I was wondering if Vb.net could do it.

Visual Basic 6 Dynamic Variables

I am doing a program using vb6 which is stored datas from mouseclick in term of coordinates. I succeeded doing the first stage which is displaying the clicked coordinates. My problem now is I need to save the coordinate in term of variables so i can call them back to use for another purpose for example to find distance between two points.
if its just two coordinates its easier to find the distance. but when it comes to many coordinates I am stuck. I tried to do an array to stored the data inside loop
1. InputX(ListNum, 0) = Int(x)
2. InputY(ListNum, 1) = Int(y)
3. ListNum=ListNum+1
when I try to call for InputX(2,0) = Text1.Text or Text1.Text=InputX(2,0) none of them working. It seems that the data will be erased after I do a mouseclick
Is there any way which I can set the dynamic variables which stored each my clicked coordinates such as Input1,Input2,Input3 ...InputN
I do this in VB6.
The problem you're having is that you're using a two dimensional array there. A two dimensional array looks like a table. That's not what you want though. You want a list of pairs of points. So, create a structure with two integers in it, x and y, and make an array of those structures:
'Right underneath your Class Form1 declaration:
Structure Point
Dim x As Integer
Dim y As Integer
End Structure
Dim length As Integer = 10
Dim Points(length) As Point
'When you want to start using your points put this in the method:
Points(0).x = 10
Points(0).y = 10
Points(1).x = 20
Points(1).y = 40
Dynamic variables in VB6
First you declare the variable without giving size:
Dim InputX() As String
Then you give for the first time size to your array using ReDim:
ReDim InputX(5)
If you want to preserve whatever data is already in your array you use ReDim Preserve:
ReDim Preserve InputX(10)
I hope this is what you need.
it appears that the first method
Text1.Text=InputX(2,0)
is working. I just need to declare x and y As Single