# Plotting

An exhaustive list of commands to do with plotting your data - one of the primary functions of Horace!

## Contents

## plot

Plot a dnd or sqw object. This does not work for 0-dimensional objects (single points), or 4-dimensional objects (we couldn't think of a way of displaying 4 dimensions plus intensity!). For 1-dimensional objects a series of markers with errorbars are connected by a line. For 2-dimensional objects a 2D colourmap is displayed. For a 3-dimensional object the *sliceomatic* program is used, where a series of 2D slices within a box are plotted.

plot(w) [figureHandle_, axesHandle_, plotHandle_] = plot(w)

The second line of code (with outputs) gives outputs that are Matlab handles to the figure window, the axes, and the plot respectively. These are useful if, for example, you wish to resize the axes, change the font size of labels, etc.

## smooth

wsmooth=smooth(w) wsmooth=smooth(w,[wid_x,wid_y,..],shape)

`smooth`

allows you to smooth the data for plotting. Can optionally specify the width and smoothing function ('hat' or 'gaussian'). The default is 'hat', and 3 bins either side in all directions.

**IMPORTANT NOTE** You can only apply smoothing to dnd objects, **not** to sqw objects, since with the latter you would be destroying the very pixel information that the object is designed to hold. To convert an sqw object (`win`

) to a dnd, simply type ` wout=d1d(win)`

, if `win`

is 1-dimensional, `wout=d2d(win)`

if it is 2-dimensional, and so on.

# Altering plot characteristics and other useful commands

## Colour of lines and markers

To change the marker and line colour in a 1-dimensional Horace plot, type

acolor <the color that you want>

e.g. for a red plot:

acolor red

## Line style

To change the line style in a 1-dimensional plot, type e.g.

aline --

to make a dashed line. You can also change the line thickness with something like

aline 2

To change multiple characteristics, type e.g.

aline(2,'--')

Type `help aline`

in Matlab for a full list of options.

## Marker style

You can change the style of marker in a 1-dimensional plot in a similar way to the above, e.g.

amark o %gives a circular marker amark 6 %sets marker size to 6 amark(6,'o') %sets a circular marker with size 6

Type `help amark`

in Matlab for a full list of options.

## Axes Limits

To change the x, y, or z limits of a plot, type e.g.

lx 0 3 ly -6 1 lz -2 2

which sets the x-axis limits to be 0 to 3, the y-axis limits to be -6 to 1, and the z-axis limits to be -2 to 2. Note the `lz`

is used to change the color scale on a colormap plot.

To set the range to cover the full data range, just issue the commands without a range:

lx ly lz

You can also change the axes scales to be linear or logarithmic using

linx logx liny logy ...

## Cursor

In order to get a cursor on your Horace plots, type

xycursor

You then left click the mouse on a position in a figure, and the x and y values are printed in the Matlab window. You can do this multiple times. To turn off the cursor, hit the carriage return key.

Alternatively, to use a cursor to select x and y values and print them in the Matlab command window or save to arrays, type

xyselect [x,y]=xyselect

## Keeping plots

To store a figure in your current session (i.e. so that the next plot you make opens in a new window, with the current plot preserved), type

keep_figure

If you have multiple figures open and you wish to alter one of them (e.g. by appending a line or more data to it)that has been kept using the above command, click on it and then type

make_current

Note that both of these options are also available in drop-down menus in the figures windows themselves.

# 1-dimensional plots

## pd

Overplot command for 1-dimensional objects only (in addition to `plot`

). Designed to mimic the `p`

command from Genie, plotting markers, errorbars, and connecting lines. This means that if you use it for two objects in succession without closing the first plot window, it will overplot the second object on the first, provided it is also a plot of a 1-dimensional object. If there is no current figure window then it plot a new one. If you use this command and the current figure window does not correspond to a 1-dimensional object, then a new figure window will also be created.

pd(w_1d) [figureHandle_, axesHandle_, plotHandle_] = pd(w_1d)

## pl

Overplot line between points for a 1-dimensional object. No markers or errorbars displayed.

pl(w_1d) [figureHandle_, axesHandle_, plotHandle_] = pl(w_1d)

## pm

Overplot markers at points for a 1-dimensional object. No line or errorbars displayed.

pm(w_1d) [figureHandle_, axesHandle_, plotHandle_] = pm(w_1d)

## pp

Overplot markers and errorbars for a 1-dimensional object. No lines linking points are displayed.

pp(w_1d) [figureHandle_, axesHandle_, plotHandle_] = pp(w_1d)

## pe

Overplot errorbars at points for a 1-dimensional object. No linking lines or markers are displayed.

pe(w_1d) [figureHandle_, axesHandle_, plotHandle_] = pd(w_1d)

## ph

Overplot histogram of a 1-dimensional object.

ph(w_1d); [figureHandle_, axesHandle_, plotHandle_] = ph(w_1d)

## ploc

Overplot `pl`

, overplotting current figure regardless of type (i.e. can plot a 1d curve on top of a 2d dataset, such as when plotting a dispersion relation over a 2d Q-E slice).

ploc(w_1d);

## peoc

Overplot `pe`

, overplotting current figure regardless of type.

peoc(w_1d);

## phoc

Overplot `ph`

, overplotting current figure regardless of type.

phoc(w_1d);

## pmoc

Overplot `pm`

, overplotting current figure regardless of type.

pmoc(w_1d);

## dd

Does exactly the same as the command `pd`

, except that it does not overplot.

## dh

Does exactly the same as the command `ph`

, except that it does not overplot.

## dl

Does exactly the same as the command `pl`

, except that it does not overplot.

## dm

Does exactly the same as the command `pm`

, except that it does not overplot.

## dp

Does exactly the same as the command `pp`

, except that it does not overplot.

## de

Does exactly the same as the command `pe`

, except that it does not overplot.

# 2-dimensional plots

## da

Area plot for a single 2-dimensional object, with colour-scale signifying intensity. It is this that is called when `plot`

is used for a 2-dimensional object.

da(w_2d); [figureHandle_, axesHandle_, plotHandle_] = da(w_2d)

## ds

Surface plot for a sinlge 2-dimensional object, with colour scale and contour signifying intensity.

ds(w_2d); [figureHandle_, axesHandle_, plotHandle_] = ds(w_2d)

## ps

Overplot a surface plot of a d2d dataset or array of datasets

ps(w)

Optionally return figure, axes and plot handles:

[fig_handle, axes_handle, plot_handle] = ps(w,...)

## spaghetti_plot

Plots data in sqw-file or sqw-object along HKL directions.

wsp = spaghetti_plot([0 0 0; 0.5 0.5 0.5; 0.5 0.5 0],sqw_file,'labels',{'\Gamma','R','M'})

# 3-dimensional plots

## sliceomatic

Sliceomatic plot of multiple area plots, for a 3-dimensional object. This function is called by the `plot`

routine.

sliceomatic(w_3d);

## sliceomatic_overview

As `sliceomatic`

, but the default view is from above. In effect this means you see a 2d slice which can be animated/changed by the third slider bar. Useful for e.g. following a spin wave dispersion ring/cone as a function of energy.

sliceomatic_overview(w_3d);

## ps2

(Note that this routine is especially useful for making surface plots of dispersion relations, when used in conjunction with `dispersion`

Make a surface plot of a 2d SQW object, with the error array (or another data source) providing the intensity

ps2(w) % Use error bars to set colour scale ps2(w,wc) % Signal in wc sets colour scale (sqw or d2d object with same array size as w, or a numeric array)

Differs from ps in that the signal sets the z axis, and the colouring is set by the error bars, or another object. This enable a function of three variables to be plotted (e.g. dispersion relation where the 'signal' array hold the energy and the error array hold the spectral weight).

One can optionally return figure, axes and plot handles:

[fig_handle, axes_handle, plot_handle] = ps2(w,...)

# Miscellaneous functions

`meta(fig)`

allows you to copy the figure into a metafile. On Windows, this function puts the file in the clipboard so that it can be pasted directly into Word, Powerpoint etc.