Overplots an existing graph produced by Display()
| PLOT | [wksp=Workspace] [binning=Integer] | Overplots with new data |
| [/HISTOGRAM] | Plots as a histogram (default) | |
| [/LINE] | Plots as a line | |
| [/MARKERS] | Plots as markers | |
| [/ERRORS] | Plots as error bars |
example:
# Plot a vanadium spectrum on top of
# the data as a comparison
>> Display s(5) xmin=20000.0
>> Plot/Line get("vanadium1","normal.in3")
Note: Plot does not allow any change of scaling.
The Plot() command is really an adjunct to the Display() command. It is used to plot just the data plot of a spectrum such that it can be used to superimpose new data onto existing plots made with with the Display() command. The Plot() command itself has no ability to create axes or scale the data.
/Histogram
This is the default as for the Display() command when given bin-mode (histogrammed) data. It will plot a spectrum making the assumption that it is a valid histogram (i.e. binned data with one more X value than Y value). The data values are represented by the height of the corresponding bin. Remember that several commands can actually affect the height of bins unexpectedly by changing the binning method and/or data. Examples of these are Alter/Binning and Units/Channel.
If point-mode data is supplied with the /Histogram qualifier an error will be reported as it is not possible for Open GENIE to guess the assumptions you may want to make about the conversion (an extra X value would have to be generated by interpolation).
/Line
This is the default for the Plot() command when given point-mode data. It will plot a spectrum as if it is a numerically calculated function (i.e. with the same number of X-values as Y-values) and join the points with a straight lines. If histogram data is displayed with the /Line qualifier, the data will undergo a transformation to take the bin centre positions as the X-values for the data points (see the Centre_bins() function). There are situations where you may not wish this behaviour to be the default (e.g. for logarithmic binning). Generally, it is safer to transform the data yourself into point-mode and then use Display to plot it.
/Markers
This is identical to the /Line qualifier in operation except that instead of joining the data points with lines, marker symbols are used instead. See Marker Types for a list of available styles.
/Errors
This is identical to the /Line qualifier in operation except that instead of joining the data points with lines, error bars are generated. These are centered on the data points and have a size scaled from the values of the data error values contained within the workspace E array.
Wksp (Workspace)
The workspace containing the data to overplot with.
Binning (Integer)
Binning for this plot only. See Alter/Binning for more details on binning. Note that by binning differently with the Plot() command, data may appear quite differently. This is because the implicit micro-averaging in the binning may substantially reduce the height of sharp peaks or noise.