{x: xScale, y: yScale, fx: fxScale, fy: fyScale},

{x = {}, y = {}, fx = {}, fy = {}, grid, facet: {grid: facetGrid} = {}} = {}

) {

let {axis: xAxis = true} = x;

let {axis: yAxis = true} = y;

let {axis: fxAxis = true} = fx;

let {axis: fyAxis = true} = fy;

if (xAxis === true) xAxis = "bottom";

if (yAxis === true) yAxis = "left";

if (fxAxis === true) fxAxis = xAxis === "bottom" ? "top" : "bottom";

if (fyAxis === true) fyAxis = yAxis === "left" ? "right" : "left";

return {

...xScale && xAxis && {x: new AxisX({grid, ...x, axis: xAxis})},

...yScale && yAxis && {y: new AxisY({grid, ...y, axis: yAxis})},

...fxScale && fxAxis && {fx: new AxisX({name: "fx", grid: facetGrid, ...fx, axis: fxAxis})},

...fyScale && fyAxis && {fy: new AxisY({name: "fy", grid: facetGrid, ...fy, axis: fyAxis})}

};

if (fxAxis) autoAxisTicksK(fx, fxAxis, 80);

if (fyAxis) autoAxisTicksK(fy, fyAxis, 35);

if (xAxis) autoAxisTicksK(x, xAxis, 80);

if (yAxis) autoAxisTicksK(y, yAxis, 35);

if (axis.ticks === undefined) {

const [min, max] = scale.scale.range();

axis.ticks = Math.abs(max - min) / k;

}

if (fx) {

autoAxisLabelsX(fx, scales.fx, channels.get("fx"));

if (fx.labelOffset === undefined) {

const {facetMarginTop, facetMarginBottom} = dimensions;

fx.labelOffset = fx.axis === "top" ? facetMarginTop : facetMarginBottom;

}

}

if (fy) {

autoAxisLabelsY(fy, fx, scales.fy, channels.get("fy"));

if (fy.labelOffset === undefined) {

const {facetMarginLeft, facetMarginRight} = dimensions;

fy.labelOffset = fy.axis === "left" ? facetMarginLeft : facetMarginRight;

}

}

if (x) {

autoAxisLabelsX(x, scales.x, channels.get("x"));

if (x.labelOffset === undefined) {

const {marginTop, marginBottom, facetMarginTop, facetMarginBottom} = dimensions;

x.labelOffset = x.axis === "top" ? marginTop - facetMarginTop : marginBottom - facetMarginBottom;

}

}

if (y) {

autoAxisLabelsY(y, x, scales.y, channels.get("y"));

if (y.labelOffset === undefined) {

const {marginRight, marginLeft, facetMarginLeft, facetMarginRight} = dimensions;

y.labelOffset = y.axis === "left" ? marginLeft - facetMarginLeft : marginRight - facetMarginRight;

}

}

if (axis.labelAnchor === undefined) {

axis.labelAnchor = scale.type === "ordinal" ? "center"

: scale.invert ? "left"

: "right";

}

if (axis.label === undefined) {

axis.label = inferLabel(channels, scale, axis, "x");

}

if (axis.labelAnchor === undefined) {

axis.labelAnchor = scale.type === "ordinal" ? "center"

: opposite && opposite.axis === "top" ? "bottom" // TODO scale.invert?

: "top";

}

if (axis.label === undefined) {

axis.label = inferLabel(channels, scale, axis, "y");

}

let candidate;

for (const {label} of channels) {

if (label === undefined) continue;

if (candidate === undefined) candidate = label;

else if (candidate !== label) return;

}

if (candidate !== undefined) {

const {invert} = scale;

if (scale.type !== "ordinal" && (key === "x" || key === "y")) {

if (axis.labelAnchor === "center") {

candidate = `${candidate} →`;

} else if (key === "x") {

candidate = invert ? `← ${candidate}` : `${candidate} →`;

} else {

candidate = `${invert ? "↓ " : "↑ "}${candidate}`;

}

}

}

return candidate;