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Tagged: Log negative
I’d like to display values from -1000 tot 1000 in my graph on a logarithmic scale.
I understand that I cannot take the log of a negative number.
Is it possible to plot a negative value?
i can imagine something like
fictional_Log(100) = log(absolute(100))*1 = 2; (and see 100 as value in the graph within an logarithmic scale )
fictional_Log(-100) = log(absolute(-100))* -1 = -2; (and see -100 as value in the graph)
with kind regards,
A logarithmic axis can only plot positive values. There simply is no way to put negative values or zero on a logarithmic axis.
Fundamental: If 10L = Z, then L is the logarithm (base 10) of Z. If L is a negative value, then Z is a positive fraction less than 1.0. If L is zero, then Z equals 1.0. If L is greater than 0, then Z is greater than 1.0. Note that there no value of L will result in a value of Z that is zero or negative. Logarithms are simply not defined for zero or negative numbers.
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