There is also the GNUPlot application for science and computing. This is an open source application for plotting and simple math.
As it's a zip file, you don't need to install on PC, it's almost portable 
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There is also the GNUPlot application for science and computing. This is an open source application for plotting and simple math.
As it's a zip file, you don't need to install on PC, it's almost portable 
Yeah, I have been using this, it's great - seems to work portably out of the box.