Few days ago, I saw a beautiful homemade science experiment on Sand Pendulums on Bruce Yeany’s YouTube channel. Go ahead and check it out. It is a cool project to do with your kids.
I will try this experiment with kids during school term holidays around Easter. But first, I wanted to try the simulation in Excel.
Simulating sand pendulum pattern in Excel
Take a look at the final simulation.
Pendulum pattern – Lissajous curve
The patterns generated by sand pendulum are nothing but Lissajous curves. We can generate these curves in Excel by using below equations.
- X = A * SIN(a*t + d)
- Y = B * SIN(b*t)
where
- A & B refer to amplitude (the length pendulum travels before reversing its direction) along X & Y axes
- a & b refer to height of pendulum along X & Y axes (if these are same you get a simple pendulum and thus a straight line pattern)
- d refers to degrees of shift (its a bit complex to explain here, but read about phase shift on Lissajous curve Wikipedia page)
- t refers to radians (degrees).
But this will generate a smooth line, how to show sand?
Simple, after computing each pair of (X, Y) we add a small random noise to them. This creates an impression of sand falling from pendulum on to a surface and bouncing off. Let’s define our new equations as,
- X = A * SIN(a*t + d) + jx * rand()
- Y = B * SIN(b*t) + jy *rand()
Where jx & jy are jitter fractions (very small numbers, lest the dots will be too away from original points)
What if the pendulum never stops?
Since we are simulating the movement of a pendulum in Excel, we can choose to have a never stopping pendulum (ie a simple gravity pendulum). In this case A & B values never change.
In real life, A&B will reduce with each oscillation until the pendulum comes to a stop (because there is air drag, friction and other forces at play too).
Let’s look at the chart & VBA
Enough physics & maths. Let’s take a look at the chart & VBA behind this simulation.
- Set up 3 columns, one with t values starting from 0 and increasing by 0.05 per cell, next two with X & Y values.
- Leave the X&Y values blank. We will use VBA to fill these.
- Let’s say we use 5000 (x,y) values to plot the chart. This gives enough variation. You can alter the number of rows later.
- Create a scatter plot with smoothed line using these 5000 (x,y) values.
- Using VBA, iterate thru column t and calculate X & Y values for each t value using above equations.
- Update the chart by using doEvents after every n calculations. Try n=25 first and change as you see fit. Updating the chart after every calculation slows down the animation significantly.
- Change A, B, a, b, d, jx, jy and air drag factors to generate different curves.
Here is the VBA code used for the animation.
Sub animate()
Dim xVal As Double, yVal As Double, jx As Single, jy As Single
Dim t As Range
Dim a1 As Single, drag As Single
Dim a2 As Double, b2 As Double, d As Double
Dim updateScreen As Integer
Dim tVals As Range
a1 = 1
drag = Range("air.drag")
a2 = [a.2]
b2 = [b.2]
jx = [j.x]
jy = [j.y]
d = WorksheetFunction.pi() / Range("d")
Set tVals = Range("t.vals")
Range(tVals.Offset(, 1), tVals.Offset(, 2)).ClearContents
Range("done") = "drawing..."
For Each t In tVals
xVal = a1 * Sin(t * a2 + d) + jx * Rnd()
yVal = a1 * Sin(t * b2) + jy * Rnd()
t.Offset(, 1).Value = xVal
t.Offset(, 2).Value = yVal
'update screen after every 25 times this loop has run
updateScreen = IIf(updateScreen = 25, 0, updateScreen + 1)
If updateScreen = 0 Then DoEvents
'Reduce A & B values by using drag
a1 = a1 * (1 - drag)
Next t
Range("done") = "done"
End Sub
Download Pendulum Sand Patterns Workbook
Click here to download the Pendulum Sand patterns workbook. Play with the animate & random pattern buttons to see some cool patterns.
Have you done this experiment?
This is a cool way to teach kids the awesome pattern power of simple things in life. Have you done this experiment? If not, give it a try. If you think playing with sand is too messy, try the Excel workbook.
Also check out: 3D dancing pendulums post to see some cool & clever animations. Huge collection of spreadsheet tools & simulations for teachers.
38 Responses to “Time to showoff your VBA skills – Help me fix ActiveSheet.Pictures.Insert snafu”
I tried your code with 2003, it works.
But, I know Addpicture does not take URLs anymore with 2007 onwards, perhaps its the same with picture.insert as well.
http://support.microsoft.com/kb/928983/en-us
The above link gives the solution as "picture fill in a shape such as a rectangle".
Tried to recreate this, but it worked fine for me. I just took the image of the error you showed in the post. Is there more info that can narrow this down a bit?
Don't know if this helps?
http://www.theserverside.com/discussions/thread.tss?thread_id=47101
Hi
Not sure if this is what you're after, but I just tried this
Sub Macro1()
ActiveSheet.Pictures.Insert("http://www.google.co.uk/intl/en_uk/images/logo.gif").Select
End Sub
Tied a button to it on the sheet and it seems to work; hope this helps a little
Ian
@All.. the issue is in Excel 2007. In 2003 ActiveSheet.Pictures.Insert seems to work fine. Unfortunately, I have design this in Excel 2007.. that is why I posted it here..
v2
Sub Macro1()
Set n = ActiveSheet.Pictures.Insert("http://www.google.co.uk/intl/en_uk/images/logo.gif")
With Range("c12")
t = .Top
l = .Left
End With
With n
.Top = t
.Left = l
End With
End Sub
Ian
That didn't come out very well. This positions at c12, so can change easily:
Sub Macro1()
Set n = ActiveSheet.Pictures.Insert("http://www.google.co.uk/intl/en_uk/images/logo.gif")
With Range("c12")
t = .Top
l = .Left
End With
With n
.Top = t
.Left = l
End With
End Sub
Works OK in 2007
Ian
The above codes work fines to my EXCEL 2007. Thanks.
Chandoo:
Try 'ActiveSheet.Pictures.Insert'
With ActiveSheet.Pictures.Insert("C:\Example.png")
.Left = ActiveSheet.Range("A1").Left
.Top = ActiveSheet.Range("A1").Top
End With
activesheet.pictures.insert "C:\Documents and Settings\Jon Peltier\Desktop\2007 stuff\insert_charts_2007.png"
Works for me in 2003 SP3 and in 2007 SP2.
Check the URL, and make sure you have internet connectivity.
What also works, and is newer (pictures.insert was supposedly deprecated in '97):
activesheet.shapes.addpicture "C:\Documents and Settings\Jon Peltier\Desktop\2007 stuff\insert_charts_2007.png", false, true, 200,200,100,100
Unfortunately you must specify dimensions (the last four arguments) and you don't necessarily know them. But the picture size is still related back to the original picture size, so you could use scaleheight and scalewidth to fix this.
Chandoo: I just re-read your post.
The code I posted works for me. However, I'm using a local picture. If you try to add a picture from the web, this won't work.
I remember solving this problem before by adding a rectangle shape first, then using the Shapes.AddPicture method to get a picture from the web.
I'll find that code and post it here.
Some more updates... The code "ActiveSheet.Pictures.Insert (path)" works fine in Excel 2007 at home. Strange it failed miserably on my work laptop. Do you think this has got something to do with SP2 of MS Office 2007 or something like that?
@Ian, Jon: Thanks for the code snippets. I guess I will use my home installation of excel to do this.
Chandoo:
Try this on your work laptop:
Sub test()
ActiveSheet.Shapes.AddShape msoShapeRectangle, 50, 50, 100, 200
ActiveSheet.Shapes(1).Fill.UserPicture _
"http://www.datapigtechnologies.com/images/dpwithPig6.png"
End Sub
FYI:
http://support.microsoft.com/kb/928983/en-us
I didn't mean to post code with a local file, because both approaches worked with an internet image as well. This is in Excel 2007 SP2.
activesheet.pictures.insert "http://peltiertech.com/images/2009-07/col_area_noblanks.png"
Jon: Looks like I have SP1 on my client machine! I wasn't paying attention.
Just checked my home computer where I have SP2, and you're right...looks like they fixed it.
I didn't even bother testing in SP1, though I could if anyone cares enough.
I'm afraid I don't have a solution, but I find it remarkable that after attaining a certain status in the Excel world, Chandoo does not need to post on an Excel discussion forum to get help for an Excel problem. Instead, he posts on his blog and all the gurus come rushing to his help.
Isn't Web 2.0 great?
Teylyn - I saw Chandoo's tweet first, and followed the link back to his blog.
@Mike.. thank you. I have seen the fill rectangle solution before posting the query here. For that matter, I have also tried the solution of embedding a browser control on a spreadsheet. both of these seemed a bit extreme. That is why I have asked it here.
But I guess I will end up using it if I had to build this in work laptop.
@Teylyn: I have thought of posting this in a forum. (Unfortunately I have not been to any excel group in the last 5 years. Last time I was active was when I built a jave based excel sheet construction solution using POI.HSSF classes of Apache... ) After searching for a few hours, I found several forum posts where others had same problem and the solution recommended (using .left and .top parameters) is not working for me. Incidentally most of these solutions are from a certain Jon Peltier 😛
I thought may be the problem is interesting for fellow blog readers. So I posted it here.
Hi,
Adapting the code in the question,
[code]
Sub InsPicture()
pPath = "http://chandoo.org/images/pointy-haired-dilbert-excel-charts-tips.png"
With ActiveSheet.Pictures.Insert(pPath)
.Left = Range("a1").Left
.Top = Range("a1").Top
End With
End Sub
[/code]
Seems to work fine
Looks like it was a problem in 2007 up to SP1, which was corrected in SP2.
@Jon.. seems like the case. I just checked the version at work laptop. it is 12.0.6331.5000 (SP1).
Thank you so much every one. I really appreciate your time and suggestions in solving this.
Glad to help. I couldn't understand why something so straightforward wasn't working.
Hi All
Is there a way of inserting a motion clip eg animated gif or swf or flv?
Thks
You can insert animated GIFs by inserting them in a browser control through VBA. For other types of movies, I can guess you can insert them as clip art.
I WANT THE INSERT PICTURE BY USING COADING
so currently i was struggling same as you, chandoo, with the insert picture method in excel 2007/10 from an url and came along your thread here.
so i re-designed the code on the addshape method as mike was suggesting it and all of the sudden it works just fine.
thanks alot to you guys, you were a great help
a big salut from switzerland
Hi guys,
I need help copying and pasting an image with the path in a cell.
I leave the code.
And thank you very much!
Sub Copiarimg()
Dim pic As Picture
With ActiveSheet
Set pic = .Pictures.Insert(Range("f2").Value)
With .Range("e9:g22")
pic.Top = .Top
pic.Left = .Left
pic.Width = .Width
pic.Height = .Height
End With
End Sub
I've played around with the approaches in these comments, and the code below is what I've come up with. The ImagePath can be a local file or a URL. As Jon mentioned above, the trick is to set an arbitrary value for the width and height, then call the ScaleWidth and ScaleHeight methods afterward to reset the picture to its original size. Once the LockAspectRatio property is set, you can change the picture width and the height will automatically scale (or vice-versa).
Sub AddPictureToRange(TopLeftCellAddress As String, ImagePath As String)
Dim pic As Shape
Dim l As Single, t As Single
Dim temp As Single
l = Me.Range(TopLeftCellAddress).Left
t = Me.Range(TopLeftCellAddress).Top
temp = 10# ' arbitrary value
Set pic = Me.Shapes.AddPicture(ImagePath, msoFalse, msoTrue, l, t, temp, temp)
pic.ScaleHeight 1#, msoTrue
pic.ScaleWidth 1#, msoTrue
pic.LockAspectRatio = msoTrue
End Sub
I need some help with inserting pictures. I have an excel file with a column of item numbers next to this row I want to insert a picture of this item. The pictures are coded with the item number so I tried to insert it with one of the codes above:
Sub InsPicture()
pPath = "http://img.bricklink.com/P/80/55236.gif"
With ActiveSheet.Pictures.Insert(pPath)
End With
End Sub
That worked but I need to do that for every row separtly.
So I tried in the code
pPath = "http://img.bricklink.com/P/80/"&Text(a1;"#")&".gif"
But that gives errors.
Anybody ideas?
Hi Nicholas, I used your solution in a related problem in Excel 2003 and it worked flawlessly..thank you!
Hi Mike Alexander,
Your solution with some changes was helpful in my problem in XL 2007, thanks.
Hi,
thanks all. In addition, I had a problem with multiple pictures inserting (every new picture replaced the prior one). I've changed it a bit, may be helpful..
Sub test()
ActiveSheet.Shapes.AddShape msoShapeRectangle, 50 , 50, 100, 200
ActiveSheet.Shapes(1).Fill.UserPicture _
"http://www.datapigtechnologies.com/images/dpwithPig6.png"
ActiveSheet.Shapes(1).Copy
ActiveSheet.Paste
End Sub
Try this instead:
Sub test()
ActiveSheet.Shapes.AddShape msoShapeRectangle, 50 , 50, 100, 200
ActiveSheet.Shapes(ActiveSheet.Shapes.Count).Fill.UserPicture _
"http://www.datapigtechnologies.com/images/dpwithPig6.png"
End Sub
Thanks to everyone, this thread has been very helpful. However, image inserting still doesn't work quite as expect for me.
While I can get a picture inserted into an Excel 2010 worksheet using either:
1) ActiveSheet.Shapes(ActiveSheet.Shapes.Count).Fill.UserPicture...
2) ActiveSheet.Pictures.Insert(pPath), and
3) Shapes.AddPicture...
unfortunately the images all insert with a display size determined not by the actual pixel dimensions of the image but by the dpi resolution.
So for example, if I insert two copies of the exact same 600x600 pixel image, one with a 300dpi resolution and the other with 72dpi, they display at vastly different sizes on screen.
While this might be intended behaviour for Excel in order to maintain a WSYWIG printing layout, I actually need a way to insert the image based on the the actual pixel dimesnsions and ignoring the dpi resolution.
Any help appreciated.
Thanks
Kez
Not doing an intentional bump, but realised I posted in rely to one of the repsonses here instead of to the main thread, so reposting.
=====
Thanks to everyone, this thread has been very helpful. However, image inserting still doesn’t work quite as expected for me.
While I can get a picture inserted into an Excel 2010 worksheet using any of the below methods:
1) ActiveSheet.Shapes(ActiveSheet.Shapes.Count).Fill.UserPicture....
2) ActiveSheet.Pictures.Insert(pPath), and
3) Shapes.AddPicture....
unfortunately the images all insert with a display size determined not by the actual pixel dimensions of the image but by the dpi resolution.
So for example, if I insert two copies of the exact same 600×600 pixel image, one with a 300dpi resolution and the other with 72dpi, they display at vastly different sizes in Excel on screen.
While this might be intended behaviour for Excel in order to maintain a WYSIWYG printing layout, I actually need a way to insert the images based on the the actual pixel dimesnsions and ignoring the dpi resolution.
Any help appreciated.
Thanks
Kez
Well, answered my own question 🙂
For those who might be interested, you can use this function:
Public Function GetPicDims(strFilePath As String, strFileName As String) As String
GetPicDims = CreateObject("Shell.Application").Namespace((strFilePath)). _
ParseName(strFileName).ExtendedProperty("Dimensions")
End Function
to get the dimensions of the image you want to insert. Then you can parse the return string and use the width and height values to add a rectangle shape of the appropraite size, like:
ActiveSheet.Shapes.AddShape msoShapeRectangle 50, 50, iWidth, iHeight
which you then fill with the picture:
ActiveSheet.Shapes(ActiveSheet.Shapes.Count).Fill.UserPicture "c:\temp\test.jpg"
This way the picture gets inserted using the pixel dimensions and the (print) resolution gets ignored.
If desired, the GetPicDims function can be made more generic to get other ExtendedProperties.
Regards
Kez