Pie Symbol Plot

The Rose (Sector) Plot, Pie Plot and Bar Plot options are used to plot symbols which can represent 1-8 different channel values at each point. The Pie Plot (CHPIE GX) creates Pie-plot symbols where the angle of each pie section represents the relative sizes of the different channel values. The Rose (Sector) Plot (CHROSE GX) creates Rose (or Sector) plots, which are similar to Pie plots, but each section has an equal angle, and the radius of individual segments scales with the data value. The Bar Plot (CHBAR GX) plots a bar graph where the height of each bar scales linearly with the data values. The three plots make use of virtually the same parameters, including colours and scaling factors, so they may be used one after another, with minimal need for re-definition of values.

Rose or Sector Plot / Pie Symbol Plot / Bar Symbol Plot

Number of Channels

Select assay channel to plot from current database. Any value from 1 to 8 may be selected.

Script Parameter: CHROSE.NUMCHAN

Default scaling (units/mm)

The default scaling. This value is used if the "Symbol scaling" attribute for any selected channel is not defined. For Pie plots this translates to "units/segment" – the values are divided by the scaling before the relative percentages of the pie are calculated.

Values are clipped to the outlier limit, if it is defined for the given channel.

Script Parameter: CHROSE.SCALE

Pie radius (mm)

(Pie plots only) The radius for the pie plot symbols.

Script Parameter: CHROSE.PIESIZE

Single bar width (mm)

(Bar plots only). The width of a single bar, in mm.

Script Parameter: CHROSE.BARWIDTH

Stack Bars?

(Bar plots only). By default ("No") bars are plotted beside each other, with the bottoms aligned. Stacked bars are put one on top of the other. This is useful when the data has been normalized by the data sum, in which case all the (full) bars will be the same height, but with varying proportions of the different colours; somewhat like a pie plot.

Script Parameter: CHROSE.BARSTACK

Symbol edge colour

Symbol edge colour, 7 colours available "black outline" (default).

Script Parameter: CHROSE.COLOR

Mask Channel

Select a mask channel from the dropdown list. If the use of the mask channel is enabled, and set to this channel, only those data values whose corresponding mask channel value is not a dummy will be plotted or exported. Channels must have their CLASS attribute set to MASK to appear as selections in the drop-down list. If the mask channel does not exist, it will be created with its CLASS attribute set to MASK.

The default mask channel is set from the CHPREFERENCES GX (Geochem Import/Preferences...).

Script Parameter: CHROSE.MASK 

Offset symbols?

If "Yes" is selected, symbols are offset from their actual locations and replotted so that overlap is avoided. The original location and the new location are joined with a line, and a small filled circle is plotted at the original location. Care should be taken when choosing the symbol size, because if the point density is too high, all the points will get pushed to the outside edge and your plot will look like a hedgehog (it also takes a lot longer!). The algorithm should work perfectly for the pie symbols, because they are all the same size. For the rose plots and bar plots an estimate of the average size is made and used to determine spacing and locations, so some overlap may occur for high-value data locations.

Script Parameter: CHROSE.OFFSET: (0:No, 1:Yes)

Offset symbol size (mm)

This is the size of the black circle marker symbol used to show the original location of the data when Offset Symbols are used.

Script Parameter: CHIMERA.OFFSETSIZE

Plot Legend?

Choose whether to plot a legend. Calls the CHROSELEG GX. The user can specify a location and legend parameters in that GX.

Script Parameter: CHROSE.LEGEND: (0:No, 1:Yes) 

Starting angle

Specify where the first edge of the first plotted pie slice in the Rose or Pie plots begins, measured in degrees counter-clockwise from horizontal (3 o’clock). By default this value is 0.0.

Script Parameter: CHROSE.STARTANG (default 0.0)

Next>

Proceed to define scaling.

Finish

Plot the symbols. If channels or colours remain to be defined, the appropriate dialog will appear before you can plot.

Specify Channels

Channel X

Select a channel from the drop-down list. All values must be specified.

Script Parameter: CHROSE.CHANX (Where X is a value from 1 to 8)

Next>

Proceed to define colours.

<Back

Return to the main dialog

Finish

Plot the symbols. If channels or colours remain to be defined, the appropriate dialog will appear before you can plot.

Specify Scaling

(Channel Name) scaling

The scale value is taken from the "symbol scaling" attribute for the given channel. If this value is not defined, the default scaling from the first dialog screen is used.

Next>

Proceed to define colours.

<Back

Return to the main dialog

Finish

Plot the symbols. If channels or colours remain to be defined, the appropriate dialog will appear before you can plot.

Specify Fill Colours

(Channel Name) colour

Select a colour from the drop-down list. All values must be specified.

Script Parameter: CHROSE.COLX (Where X is a value from 1 to 8)

<Back

Return to the main dialog

Finish

Plot the symbols. If channels or colours remain to be defined, the appropriate dialog will appear before you can plot.

Application Notes

See Also: