PRESENT GRAPH LINE Line_definition

          

This command will produce a graph showing the variation of results along a specified line. The line can be defined as part of the command in the same way as for CONSTRUCT LINE, it can be the OLD line (the last line to be constructed, viewed or graphed along), or it can be specified by name for lines previously saved to the database.

Notes:

1.

Superimposition of graphs
Where a range of loadcases has been specified, the graphs for each set of results will be superimposed.
Also, more than one named line may be specified as part of the command, and if so graphs along each of these lines will be superimposed. Graphs for a maximum of 20 named lines can be superimposed in this way.

2.

Graphs of more than one attribute
The results graphed will be the currently selected results superimposed with any results previously added to the RESULTS STACK. In this way multiple attribute graphs are possible.

3.

Calculation of distance
The distance along the line is calculated as the cumulative distance between each node or element centroid, in the order that they were specified. If the nodes or elements are given in a different order then this distance will change.

4.

Graphs of nodal results
Graphs of nodal results are only possible along a line of nodes or a free line.

5.

Graphs of element nodal results
Graphs of element nodal results are possible along all three types of line.

For graphs along a line of nodes, the database is searched to find elements with edge definitions that match the segments (e.g.: n1 to n2) of the specified line. All elements encountered in the database with the appropriate edge nodes for a line segment are selected and the results for these elements used in the graph. Therefore several lines may be drawn on the graph for each segment of the specified line. Thus, where a line is common to more than one element, to ensure that only the results for the required elements are graphed, these elements can be placed into a set, which should then be viewed before issuing the PRESENT GRAPH LINE command.

For graphs along a line of elements, one representative results value is taken for each element, which can be set to be either the (absolute) maximum, (absolute) minimum, mean value or nth value of the results at each of the element's nodes using the command RESULTS RANGE EL-RESULT.

For graphs along a free line, results values at each element boundary that the line passes though are interpolated. Discontinuities will occur where the line passes outside the model.

6.

Graphs of element Gaussian results
Graphs of element Gaussian results are only possible along a line of elements. For each specified element one representative results value is taken which can be set to be either the (absolute) maximum, (absolute) minimum, mean value or nth value of the results at each of the element's Gauss points using the command RESULTS RANGE EL-RESULT.

7.

Graphs of element invariant results
Graphs of element invariant results are only possible along a line of elements.

8.

Graphs of nodal material dependent results
Where the results values are nodal material dependent, the required material may be specified with the RESULTS RANGE MATERIAL command. If no material number is specified then all of the materials encountered at each node will be used, and the line may be discontinuous at material boundaries.

9.

Graphs of results for multiple surfaces
Where there are results values for more than one surface, the required surface or surfaces may be specified with the RESULTS RANGE SURFACE command. If no surface number is specified then all of the surfaces encountered will be used.

Examples:

1.

PRESENT GRAPH LINE OLD

A graph of the currently selected results and those previously stored in the results stack for the selected loadcases against distance along the current line is drawn.

2.

PRESENT GRAPH LINE NODES LIST 1 TO 20

A graph of results against distance along the line of nodes from 1 to 20 is drawn.

3.

PRESENT GRAPH LINE top_edge bot_edge

A graph of results against distance along the previously saved lines `top_edge' and `bot_edge' is drawn.

See also the following commands

'CONSTRUCT LINE'
'PRESENT OPTIONS GRAPH'
'RESULTS RANGE'
'RESULTS STACK'