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# semilogx

Semilogarithmic plot

## Syntax

```semilogx(Y) semilogx(X1,Y1,...) semilogx(X1,Y1,LineSpec,...) semilogx(...,'PropertyName',PropertyValue,...) semilogx(ax,...) h = semilogx(...) ```

## Description

`semilogx` plot data as logarithmic scales for the x-axis.

`semilogx(Y)` creates a plot using a base 10 logarithmic scale for the x-axis and a linear scale for the y-axis. It plots the columns of `Y` versus their index. The values in `Y` can be numeric, datetime, duration, or categorical values. If `Y` contains complex values, then `semilogx(Y)` is equivalent to `semilogx(real(Y),imag(Y))`. The `semilogx` function ignores the imaginary component in all other uses of this function.

`semilogx(X1,Y1,...)` plots all `Yn` versus `Xn` pairs. If only one of `Xn` or `Yn` is a matrix, `semilogx` plots the vector argument versus the rows or columns of the matrix, along the dimension of the matrix whose length matches the length of the vector. If the matrix is square, its columns plot against the vector if their lengths match. The values in `Yn` can be numeric, datetime, duration, or categorical values. The values in `Xn` must be numeric.

`semilogx(X1,Y1,LineSpec,...)` plots all lines defined by the `Xn,Yn,LineSpec` triples. `LineSpec` determines line style, marker symbol, and color of the plotted lines.

`semilogx(...,'PropertyName',PropertyValue,...)` sets property values for all charting lines created by `semilogx`. For a list of properties, see Line Properties.

`semilogx(ax,...)` creates the line in the axes specified by `ax` instead of in the current axes (`gca`). The option `ax` can precede any of the input argument combinations in the previous syntaxes.

`h = semilogx(...)` return a vector of chart line objects.

## Examples

collapse all

Create a plot with a logarithmic scale for the x-axis and a linear scale for the y-axis.

```x = 0:1000; y = log(x); figure semilogx(x,y)```

## Tips

If you do not specify a color when plotting more than one line, `semilogx` automatically cycle through the colors and line styles in the order specified by the current axes `ColorOrder` and `LineStyleOrder` properties.

You can mix `Xn,Yn` pairs with `Xn,Yn,LineSpec` triples; for example,

```semilogx(X1,Y1,X2,Y2,LineSpec,X3,Y3) ```

If you attempt to add a `loglog`, `semilogx`, or `semilogy` plot to a linear axis mode graph with `hold`` on`, the axis mode remains as it is and the new data plots as linear.