plotgr

Process Help

PLOTGR - create a rotated grid plot

Process Name	Menu Path	Link to Command Table
PLOTGR	Command line onyly	Click here

Introduction
Files, Fields and Parameters
Notes
Example
Errors

Introduction

Generates a plotted grid, or set of lines, at any user-defined angle to the plot X and Y axes. Annotation on the lines may be defined and positioned by the user. Single lines may be plotted, or sets of lines at pre-defined intervals.

How to use

Typical uses include laying a mine grid over a national grid system, or vice-versa, or plotting section lines on a plan.

The relationship between the plot X and Y axes and the required lines is defined by specifying a point whose co-ordinates are known in both systems (X0, Y0 in the plot system and XR0, YR0 in the rotated system) and an angle between them, measured in degrees clockwise from the rotated system Y axis to the unrotated system Y axis. This is illustrated in the accompanying diagram. Note that the point of coincidence need not be in the plot area.

Lines in the rotated X and Y directions are specified independently by giving co-ordinates of the first and the last line required, and the increment between lines. These parameters are @XSTART, @XINC and @XEND in X; and the equivalent in Y. For no lines in either of the directions, all three are set to 0; for only one line, the co-ordinate is specified as the start (@XSTART or @YSTART) and end (@XEND or @YEND) and the increment (@XINC or @YINC) set to zero.

The given lines are intersected with the data area of the plot, as defined in the prototype, and the intersections plotted. Annotation is placed at the start of each line (unless optional parameter @NOANNOT=1). The start point of this annotation, relative to the start of the line, may be controlled if required by specifying the @XOFFSET and @YOFFSET parameters. If these are not set, then the start is taken as 1 character position along the line and half a position above.

Different Units

The @FACTOR parameter may be used to specify that the units of the grid lines are different to those of the plot (which are defined by the @XMIN,... @YMAX parameters or taken from the prototype). For example, if @FACTOR=0.3048 and user data units are meters, then the grid lines will be in feet. @FACTOR is the number of user data units which equals one unit in the plotted grid.

If @FACTOR is set, then the @XSTART, @XINC and @XEND parameters are all set in the grid units, (as are the Y equivalents) and the @XR0, @YR0 point is also defined in these units. The annotation is also shown in these units.

Use of the @FACTOR parameter allows for example section lines in feet or hundreds of feet to be plotted where the user data units are meters.

Files, Fields and Parameters

Input Files

Name	Description	I/O Status	Required	Type
PROTO	Plot prototype file. Must contain the fields X, Y, S1, S2 and CODE (numeric, explicit) and XMIN, XMAX, YMIN, YMAX, XSCALE, YSCALE (numeric, implicit). If these last 6 values set in PROTO , then corresponding parameters need not be set.	Input	Yes	Plot Prototype

Output Files

Name	I/O Status	Required	Type	Description
PLOT	Output	Yes	Plot	Output plot file.

Parameters

Name

Description

Required

Default

Range

Values

ANGLE

Rotation angle in degrees, measured from the rotated axes towards the X-Y plot axes.

Yes

Undefined

0,360

Undefined

X co-ordinate of known point in both systems, in unrotated co-ordinate system.

Yes

Undefined

Y co-ordinate of known point in both systems, in unrotated co-ordinate system.

Yes

Undefined

XR0

X co-ordinate of known point in both systems, in rotated co-ordinate system.

Yes

Undefined

YR0

Y co-ordinate of known point in both systems, in rotated co-ordinate system.

Yes

Undefined

XSTART

First required line in rotated co-ordinate system X direction. Set XSTART , XINC , XEND all to 0 for no X lines.

Yes

Undefined

XINC

Increment between grid lines in rotated co-ordinate system X direction. Set to 0 for one line only.

Yes

Undefined

XEND

Last required line in rotated co-ordinate system X direction. Set to XSTART for one line only.

Yes

Undefined

YSTART

First required line in rotated co-ordinate system Y direction. Set YSTART , YINC , YEND all to 0 for no Y lines.

Yes

Undefined

YINC

Increment between grid lines in rotated co-ordinate system Y direction. Set to 0 for one line only.

Yes

Undefined

YEND

Last required line in rotated co-ordinate system Y direction. Set to YSTART for one line only.

Yes

Undefined

NDEC

Number of decimal places for annotation.

Yes

Undefined

FACTOR

The rotated co-ordinate system units will be e.g. 0.3048 for a grid in feet on an unrotated grid in metres (1).

Undefined

NOANNOT

Option	Description
1	do not plot annotation on lines (0).

0,1

XOFFSET

The offset in millimetres of the start of the annotation from the start of each grid line measured along the line. [Default=1.0 CHARSIZE].

Undefined

YOFFSET

The offset in millimetres of the start of the annotation from the start of each grid line measured at right angles to the line. [Default=0.5 CHARSIZE].

Undefined

CHARSIZE

Character size in millimetres (3).

Undefined

ASPRATIO

Aspect ratio [width to ht.] for chars (0.9).

0.9

Undefined

Colour [as 'pen' number] for plot (1).

Undefined

APPEND

Plot append flag. If set to 1 then the new plot will be appended to the PLOT file, if it exists and is a valid plot file (0).

0,1

XMIN

Minimum value of X for plot. None of XMIN, XMAX, YMIN, YMAX, XSCALE, YSCALE need be set if this information is already in the prototype.

Undefined

XMAX

Maximum value of X for plot.

Undefined

YMIN

Minimum value of Y for plot.

Undefined

YMAX

Maximum value of Y for plot.

Undefined

XSCALE

X scale in user data units per millimetre.

Undefined

YSCALE

Y scale in user data units per millimetre.

Undefined

Notes

Lines which lie completely outside the plot area will be omitted with no message. Therefore, to plot a full grid, it is easier to specify line start and end co-ordinates which lie well outside the area of interest, and leave the process to compute those that lie inside.

If the grid is parallel to the axis (@ANGLE=0) then the first or last lines will sometimes be omitted if they lie exactly along the boundary of the plot region. This is because of slight inaccuracies in the tests for a line lying inside the plot region.

Example

!PLOTGR

&PROTO(PLOTPROT),&PLOT(GRID.P),@ANGLE=38,@X0=350, @Y0=400,@XR0=0,@YR0=0,@XSTART=-50,@XINC=50,@XEND=100, @YSTART=0,@YINC=0,@YEND=0,@NDEC=0,@XMIN=300,@XMAX=600, @YMIN=300,@YMAX=600

A set of four section lines is plotted at X=-50, X=0, X=50, and X=100. These lines are at an angle of 38 degrees from the plot X axis; the point X=0, Y=0 of the grid corresponds to X=350, Y=400 of the plot. The data region covers the user data range of 300 to 600 on both axes. There are no lines plotted on the grid Y axis.

!PLOTGR

&PROTO(PLOTPROT),&PLOT(GRID1.P),@ANGLE=0,@X0=0, @Y0=0,@XR0=0,@YR0=0,@XSTART=900,@XINC=100,@XEND=1800, @YSTART=900, @YINC=100,@YEND=1800,@FACTOR=0.3048, @CHARSIZE=2.5,@=8,@NDEC=0,@XMIN=300,@XMAX=600, @YMIN=300,@YMAX=600

A grid in feet is overlain on the metric plot (which runs from 300 to 600 meters in both X and Y). This grid is parallel to the axes. The lines are spaced at 100 foot intervals, starting at 900 feet (which will be outside the plot and therefore omitted) and running to 1800 feet in both directions. The color chosen is 8, with a character size of 2.5 mm.

Error and Warning Messages

Message	Description	Solution
>>> ERR 411 <<< ( 0) IN TRANDP	The scale has been defined or calculated as zero. Fatal; the process is exited.

>>> CANNOT APPEND TO NON-EXISTENT OUTPUT FILE. >>> A NEW OUTPUT FILE WILL BE CREATED	The @APPEND parameter has been set to 1, but the specified plot file does not exist. A new file will be created to contain the new plot being produced.

>>> ERROR - CANNOT APPEND TO PLOT FILE AS IT DOES >>> NOT CONTAIN ALL THE REQUIRED FIELDS. >>> THE PLOT FILE WILL BE OVERWRITTEN.	The @APPEND parameter has been set to 1, the specified plot file exists but is invalid. The existing plot file will be overwritten by the new plot being produced.

>>> FATAL ERROR, BAD SCALE/RANGE COMBINATION(S) <<< >>> XMIN, XMAX = nnnnnnnnnn.nn nnnnnnnnn.nn >>> YMIN, YMAX = nnnnnnnnnn.nn nnnnnnnnn.nn >>> XSCALE, YSCALE = nnnnnnnnnn.nn nnnnnnnnn.nn	Either insufficient scale information had been entered (at least two of XMIN, XMAX, XSCALE or Y equivalents must be entered either from the prototype of from parameters) or the combination given of XMIN, XMAX, and XSCALE (or their Y equivalents) was impossible. Often caused by entering a null plot prototype and no parameters. Fatal; the process is exited.