R language Low-level drawing function-axis

Axis functions are used to add axes to a chart, different from the traditional x and Y axes, and axis allows the addition of axes in the upper, lower, left, and right 4 directions

Take the x-axis for example, an axis contains 3 elements, a horizontal line, called axis line, tick marks, called tick lines, corresponding labels labels

Basic usage:

Use the side parameter to set the direction of the axis you want to add, starting at the bottom and counterclockwise, with a number from 1 to 4

code example:

Par (OMA = C (1, 1, 1, 1), Mfrow = C (1, 4)) plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) text (x = 3, y = 3, labels = "side = 1", CeX = 2) box () axis (side = 1) plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) te  XT (x = 3, y = 3, labels = "side = 2", CeX = 2) box () axis (side = 2) plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "N",  axes = F) text (x = 3, y = 3, labels = "side = 3", CeX = 2) box () axis (side = 3) plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), Type = "N", axes = F) text (x = 3, y = 3, labels = "side = 4", CeX = 2) box () axis (side = 4)

As follows:

Parameter settings:

At: A value that needs to be added to the scale, by default a few appropriate ticks are calculated based on the range of variables, or you can manually specify

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, at = C (0, 2, 4, 6))

As follows:

Lables: Specifies the content that needs to be marked on the scale, by default the value corresponding to the scale

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, at = C (0, 2, 4, 6), labels = paste ( C (0, 2, 4, 6), "A", Sep = "")

As follows:

TICK: Logical value, whether the axis is displayed, including tick marks and corresponding axes, FALSE means not showing

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = f) axis (side = 1, tick = f)

：

Line: The location of the axis

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, line = 1)

As follows:

LWD: Sets the width of axis line and tick line

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, line = 1, LWD = 2)

As follows:

Lwd.tick: Set the width of the tick line

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, line = 1, LWD = 1, Lwd.tick = 2)

As follows:

Lty: Sets the line type for axis lines and ticks

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, line = 1, lty = 3)

As follows:

Col: Sets the line color for axis lines and Tick.line

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, line = 1, col = "Blue")

As follows:

Col.ticks: Set the color of the tick line

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, line = 1, col = "Blue", Col.ticks = "Red")

As follows:

POS: Adjusts the position of the axis and overwrites the value of the line parameter when POS sets the corresponding value

code example:

Plot (1:5, 1:5, Xlim = C (0,6), Ylim = C (0,6), type = "n", axes = F) box () axis (side = 1, pos = 1)

As follows:

R language Low-level drawing function-axis