Trying to plot log function

[JosephBoom02]

I'm trying to plot the log function with this code:

#align(center)[
    #cetz.canvas({
        import cetz.draw: *
        content((3.1, 5.8), [$e^(-2t)$], name: "text")
        plot.plot(
            size: (8,6),
            x-tick-step: none, 
            x-ticks: (1, 0), 
            y-tick-step: none,
            y-min: -2,
            y-max: 2, 
            x-min: 0,
            x-max: 20,
            axis-style: "school-book",
            {
            plot.add(
                domain: (0, 20), x => calc.ln(x),
                style: (stroke: black)
                ) 
            }
        )
    })
]

but I have this error from the calc.ln function : value must be strictly positive.
What should I do?

[johannes-wolf]

Your domain starts at 0, but calc.ln accepts positive values only. You have to change your domain to e.g. (1e-12, 20).