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Notes on Desmos range from just above E4 to just above E5. The g function converts a note to the appropriate y-value. For example, g(0) gives the y-value for A4, g(1) gives the y-value for B♭4, g(2) gives the y-value for B4, etc. g(-5) is the y-value for E4, but since it is slightly off-screen (g(-5) ≈ -0.164), we round it to 0 to get a full octave.

This formula was obtained by collecting frequency data for various y-values and then conducting a regression test on Desmos, with ln f ~ ay + b. Values for a and b were found: a ≈ 0.00693157 and b ≈ 5.7991. Therefore, the frequency of a y value is given by f = e^(ay + b), and the y-value corresponding to a frequency is given by y = (ln f - b) / a. Since frequencies in 12-TET are given by 440·2^(x/12), where x is the number of half steps away from A4, the y-value corresponding to a note is then given by (ln 440 + (x/12) ln 2 - b) / a.