IMS 1.0
Intelligent Mining Software “Solutions”
IMS - Model Histograms
Produced by W.S. Mart and G. Markey
For MineMap Pty Ltd
Intelligent Mining Software “Solutions” IMS - Model Histograms
Copyright © 2013 by William Seldon Mart and Geoff Markey. All rights reserved.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
Table of Contents
INTRODUCTION.................................................................................................................... 3
RUNNING THE HISTOGRAM MODULE .......................................................................... 4
The Model Page ............................................................................................................................ 5
The Parameters Page ................................................................................................................. 6
The Axes Page ............................................................................................................................... 8
The Data Page ............................................................................................................................. 10
The Fonts Page ........................................................................................................................... 11
The Report File Page ................................................................................................................ 12
STATISTICS REPORTED ................................................................................................... 13
Histograms and Cumulative Plots ....................................................................................... 13
APPENDIX: USING HISTOGRAMS FOR QUICK TONNAGE CALCULATIONS ... 14
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Intelligent Mining Software “Solutions” IMS - Model Histograms
INTRODUCTION
The Histogram module performs statistical analysis on a model cell. It provides the distribution of the
value of the parameter, considered with respect to the total model or a portion of the model or a
specified plan file. Any stratigraphic unit type (i.e. stratigraphic units present in the seam/benches
present in the model) may be used with or without weighting for thickness.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
RUNNING THE HISTOGRAM MODULE
1. Load the required model into the 3D View Pane.
2. Select the <Model><Histograms...> menu item (Figure 1) to display the first page of the
Histogram parameters wizard.
Figure 1: Selecting the Histogram menu item
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Intelligent Mining Software “Solutions” IMS - Model Histograms
The Model Page
Figure 2: Selecting stratigraphies and restrictions
1. Select the stratigraphic units that you want to work on from the seams list (Figure 2).
2. Restrict the range of elevations if required. The elevation is is the height above sea level (or
some chosen datum) of the top of the stratigraphic unit.
3. Restrict the range of depths if required. The depth is the distance from the surface to the roof
of the stratigraphic unit.
4. Restrict the range of stratigraphic thicknesses if required.
Data values that do not satisfy the restrictions are excluded from the plot and associated statistics.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
The Parameters Page
Figure 3: Plot information
1. Enter the name of the plot file or leave it blank if a plot file is not required. Plot files are
standard EMF (Enhanced Meta Files) that can be viewed any image viewer.
2. Select the plot type. There are five plot types available:
 Histogram
 Histogram (Log Scale)
 Cumulative
 Cumulative (Log Scale)
 Scatter
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Intelligent Mining Software “Solutions” IMS - Model Histograms
3. Enter the width and height of the plot. The plot will be scaled to fit the sizes specified here.
The sizes refer to the actual graph only and do not include the axis labels, titles, etc. A
practical minimum x-axis size is about 200mm.
4. Select the title box option if required. If you choose not include the title box, the plot will be
produced without the title box border.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
The Axes Page
Figure 4: Axis parameters
1. Select the quality required to calculate the statistics. The qualities are shown in Table 1.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
Table 1: Available qualities
Data Type
Use On
Roof
Laminar Models
Floor
Laminar Models
Thickness
Laminar Models
Depth
Laminar Models
Qualities (Assays)
Laminar Models, Block Models
2. Enter the minimum and maximum values for the x-axis.
3. Enter the increment for the x-axis. This determines the interval between tick marks. Up to a
maximum of three hundred intervals can be used on each axis, (i.e.
).
4. Enter the minimum and maximum accepted values. Only data that falls between (and
including) these values are considered in the calculations.
5. Enter the upper-cut. Data values larger than the upper-cut are reassigned the upper-cut value.
6. If you selected a scatter plot type then the y-axis parameters are enabled.
a.
b.
c.
d.
Select the quality for the y-axis.
Enter the minimum and maximum values for the y-axis.
Enter the increment for the y-axis. This determines the interval between tick marks.
If you require a regression line then select the Show regression check box.
7. If you require grid lines on the plot then select the x-grid and/or the y-grid check boxes.
8. If you require a line representing the median on the histogram plot then select the Show
histogram median line check box.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
The Data Page
Figure 5: Restricting the data
Select the subset of data required for the plot. If you select Use data inside polygons then a file
selection dialog box is displayed. Enter the name of a plan file in this dialog box. The plan file must
contain at least one closed polygon to define the region of interest.
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The Fonts Page
Figure 6: Fonts for graph elements
Select the fonts for the various graph elements. Only the font name, colour and size (in points) are
currently available.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
The Report File Page
Figure 7: Reporting the statistics
1. Enter the name of the report file or leave blank if a report file is not required.
2. Enter the header line text if required.
3. Press <Finish> to start the calculations.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
STATISTICS REPORTED
The Histogram module displays the required graph on screen and saves it to the plot file if one was
specified. The statistics displayed on the graph are a subset of those used in the calculations. Consult
the report file for the extra statistics (e.g. standard deviation, the number of observations and the
median).
NOTE: If the number of observations is less than thirty then a simple standard deviation is used.
Otherwise, the Histogram module uses a population standard deviation.
Histograms and Cumulative Plots
Standard deviations are calculated as grouped data points, i.e. the midpoint of each class interval is
taken to be the datum for the calculations. However, the value added to that class interval is the
thickness for the selected cell divided by the total average thickness of all cells.
Since the calculations are performed on grouped data, the reported standard deviation will be
marginally different to that of the raw data. If a calculation of the raw data statistics is required, it is
necessary to reduce the class intervals to the minimum possible.
NOTE: The maximum number of class intervals is three hundred. This procedure will still not
produce completely comparable results but will reduce any possible errors to an absolute
minimum.
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Intelligent Mining Software “Solutions” IMS - Model Histograms
APPENDIX: USING HISTOGRAMS FOR QUICK TONNAGE CALCULATIONS
The Histogram module provides the following benefits:
 It presents the results of the analysis in a compact and easily readable form.
 The shape of the distribution is immediately apparent.
 The output is suitable for inclusion in reports without further processing.
If the analysis is weighted by thickness then the results can be used to derive the ore tonnages for each
nominated step in the parameter value(s) by applying the percentage derived for that step to the total
tonnage for the stratigraphic unit. This is achieved as follows:
1. Graph the thickness of the stratigraphic unit and the qualities (weighted by stratigraphic unit
thickness) of interest.
2. Determine the mean of each of these parameters and multiply the average thickness of the
seam by the mean quality derived.
3. Multiply the result gained by the area of interest.
This procedure supplies the tonnages provided the relative density of the quality being considered is
corrected by using the following equation:
Example
Average thickness of strat unit = 1.5m (from the Histogram module)
Average grade of product
= 10.0% (from the Histogram module)
Area of interest
= 1,000,000m2
Relative density of product
= 2 tonnes / m3
Therefore the total tonnage is
product
tonnes of
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