Huddled Masses
Posts Tagged ‘Charting’
January 16th, 2009 | 
Author: Once I started playing with the new ability, introduced in PowerBoots 0.0.4 to easily add support for new graphical controls to PowerBoots, I found all sorts of fun widgets out there in open-source land. I’ll write about a few of them in the future, but for now I’m just going to stick with Visifire. After playing with a few examples, I finally got around to actually trying to create the graphs I needed at work which were the main source of motivation for trying to do Visifire from PowerShell anyway …
The problem was, half of the need we have for graphs is to throw them up on a web-server … so I needed a way to take the WPF window, and capture the controls and visuals as an image. Basically, render the WPF control to a bitmap image, instead of to the screen. To cut a long story short, I figured it out of course — why else would I be writing this? (get it here).
Out-BootsImage
So the new version of PowerBoots includes the Out-BootsImage function (aliased as BootsImage and “obi”), which basically is designed to take the filename of an image, and a boots visual element, and create a screenshot. It can generate bmp, gif, jpg, png, tiff, and even Microsoft’s new wdp format, or it can output to clipboard.
It’s late, so I’m not going to write any more about this … the bottom line is, if you have been looking for a (free) way to generate graphs and charts to image files in PowerShell, this will work for you: go grab Visifire, check out their gallery for inspiration, and start churning out graphs! Just for fun, here are the samples from the help documentation (except, this is the actual script I ran, including the upload code) with screen-shots …
Important note
When producing images of Visifire charts using this method, it is absolutely critical that you must specify -Animation $false because otherwise you will consistenly produce images of empty charts (since by default Visifire animates all of the bars onto the screen right after the SourceInitialized event that I use to capture the image). Oh, and if you need to remove the Visifire.com watermark, there is a -watermark $false parameter on the Chart element, which turns it off.
$credential = Get-Credential
Chart -Width 200 -Height 150 -Theme Theme3 -Watermark $false -Animation $false (
DataSeries $(
1..(Get-Random -min 3 -max 6) | ForEach-Object {
DataPoint -YValue (Get-Random 100)
}
)
) | Out-BootsImage VisiFire-BootsImage.jpg |ForEach-Object {
Send-FTP HuddledMasses.org $credential -LocalFile $_ -Remotefile "$imgPath/$($_.Name)"
[Windows.Clipboard]::SetText( "!http://huddledmasses.org/images/PowerBoots/$($_.Name)!" )
}
StackPanel -Margin "10,5,10,5" $(
Label "Please enter your name:"
StackPanel -Orientation Horizontal $(
TextBox -OutVariable global:textbox -Width 150 -On_KeyDown {
if($_.Key -eq "Return") {
Write-Output $textbox[0].Text
$BootsWindow.Close()
}
}
Button "Ok" -Padding "5,0,5,0" -Margin "2,0,0,0" -On_Click {
Write-Output $textbox[0].Text
$BootsWindow.Close()
}
)
) | Out-BootsImage BootsImage-Screenshot.jpg | ForEach-Object {
Send-FTP HuddledMasses.org $credential -LocalFile $_ -Remotefile "$imgPath/$($_.Name)"
[Windows.Clipboard]::SetText( "!http://huddledmasses.org/images/PowerBoots/$($_.Name)!" )
}
Posted in Huddled | 
Tags: Charting, Charts, Development, PowerBoots, PowerShell, Visifire, WPF | 
2 Comments »
Several people have blogged about using the Google charts api from PowerShell, but everyone seems to be using the “simple” numerical encoding, so I figured that as the first step of my own google chart api wrapper module I would start out by writing up a simple encoder. I’m not posting this to the script repository until I’m done with it — this is just the number encoding function.
But I figured I’d blog it here in case it will help anyone else write the full wrapper module “for” me before I get around to it 
In any case, remember this doesn’t encode numbers higher than 4095, so if you have a bunch of numbers and some of them might be larger than that, you’ll still need to normalize them so they are within that range. I’ll post the function to normalize a series of numbers later this evening, because for some reason I can’t find it right now, but I’m sure I already wrote it 
.
## Google Chart API extended value encoding function
#########################################################################
function GoogleEncode {
BEGIN {
## Google's odydecody is a 64 character array
$ody = "A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q",
"R","S","T","U","V","W","X","Y","Z","a","b","c","d","e","f","g","h","i","j",
"k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z","0","1","2",
"3","4","5","6","7","8","9","-","."
## The actual filter function
filter encode {
# we have a hard-coded "overflow" value
if($_ -ge ($ody.Count * $ody.Count) ) { return "__" }
$y = -1 # $y is a ref variable, so it has to be defined
$x = [Math]::DivRem( $_, $ody.Count, [ref]$y )
return "$($ody[$x])$($ody[$y])"
}
## Handle numbers as parameters
foreach($i in $args) {
$i | encode
}
}
## Or handle numbers from the pipeline. We don't care :-)
PROCESS {
if($_ -ne $null) { $_ | encode }
}
}
That’s the whole thing … it’s really only about three lines of code (including the definition of $ody), but the rest is necessary to make it handle parameters or pipeline values. 