For this activity we scanned an old, handwritten graph in order to be able to extract information from it:
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| Initial Hand-drawn graph |
Using an image editor (I used GraphicsGale, an editor which is specifically designed for pixel art), we estimate the relationship between the scaling used and the pixels of the image:
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| Pixel vs Scaling ticks of the manual graph |
having obtained a scaling factor for the graph data points were (painstakingly) taken from the hand drawn graph. These data points were converted to the graph's actual scale to obtain:
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| Final digitally reconstructed graph | |
As we can see, the reconstructed graph does not fit the manually drawn graph. this may be due to estimation errors since the lines of the graph encompass more than one pixel.
All in all, I don't think of it as an overestimation if I give myself full points for this activity because, come on... I took a data point every 5 pixels so I think that counts as something. ^^
TJ,
ReplyDeleteDo the maximum values of your x and y axis correspond to the max values of the original plot? Since now you have a conversion factor for the x and y-axis, you can estimate the max value by getting the pixel coordinates of the axes ends in the image.
I commend your hardwork and detailed data gathering but to deserve full points, we have to get it exactly right. Will you show me please an improved graph?
Jing