Shifting the origin on Excel charts

[EMUGuru]

I have a scatter chart that has data that starts with negative x values. (Y values are already all positive.) What I wish to do is shift the x-axis scale on the Excel chart to essentially make the greatest negative value on the x-axis the new zero value (origin) and thus essentially shift all the x-axis values accordingly putting the entire chart in the positive XY region. Is this possible?

 

[PaddyD]

hi - welcome to the board!

select the x axis, right click, format axis | axis tab - manually set the 'crosses at' number to whatever you want.

 

[EMUGuru]

Thanks Paddy D for the welcome. I have done what you suggested. This solution does put the graph in the positive xy region, but it does not shift the x values so as to have the origin be (0,0). The subsequent result is that my chart's x-axis starts at the point (-0.01, 0) not (0,0). This procedure does not essentially revalue my x values by the offset of, in this case, 0.01. I need this to happen so I can perform future operations. I'm going to be taking a tangent of the graph and having the graph start at (0,0) rather than (-0.01, 0) would be helpful.

 

[PaddyD]

"This procedure does not essentially revalue my x values..."

Indeed not - graphs graph. If you want to change your data, you have to change your data.

"I'm going to be taking a tangent of the graph and having the graph start at (0,0) rather than (-0.01, 0) would be helpful."

Why?

 

[EMUGuru]

The chart or graph itself describes a mechanical engineering tensile test. By drawing a tangent on the initial part of the graph itself and then drawing a line parallel to the tangent at a 0.02% offset from the tangent line and following this second line to where it intersects on the graph, one achieves a value at that intersection point that is considered the yielding point of the material tested.

 

[PaddyD]

Still not sure why you need to re-base the numbers, but given a data series in a1:a10, which may or may not have negative numbers, you could re-base the series to >=0 with a formula of the form:

=A1+(-MIN(0,MIN($A$1:$A$10)))

...& plot that instead.

 

[EMUGuru]

Great! Thanks, and as I think it out I believe you are right in wondering whether it may be necessary at all to shift the values.