CONTOUR
Preprocess data for contour plots

CONTOUR is a FORTRAN90 program which preprocesses simple grid data into a form that the DISPLAY3 program can handle.

The idea is that there is a set of nodes arranged in a rectangular grid. There is a file containing the coordinates of the nodes, and the values of certain quantities at each node. Specifically, for each node, there is a line of the form:

        X  Y  V1  V2 ... VN
      

CONTOUR reads this data, tries to determine the 2D shape NX by NY of the grid essentially by factoring the number of points, arranges the data into elements, and writes out an element file and a node file suitable for input to DISPLAY.

Usage:

The name of the input file is usually specified on the command line:

        contour input_file
      

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Related Data and Programs:

CONTOUR_SEQUENCE is a MATLAB program which creates images suitable for animation from a sequence of (X,Y,U(X,Y)) data files;

CONTOUR_SEQUENCE3 is a MATLAB program which creates images suitable for animation from one pair of X, Y files, and a sequence of U(X,Y) data files;

CONTOUR_SEQUENCE4 is a MATLAB program which makes contour plots of a sequence of files defining the values of a scalar function Z(X,Y) sampled on a grid.

DISPLAY3, a FORTRAN90 program which displays graphics from the flow data computed by FLOW3. This program used to work, but it is very out of date;

NAST2D_CONTOUR, a MATLAB program which reads a data file from NAST2D_F90 and creates a contour plot;

TRIANGULATION_ORDER3_CONTOUR is a MATLAB program which makes contour plot of data defined on an order 3 triangulation.

TRIANGULATION_ORDER6_CONTOUR is a MATLAB program which makes contour plots of data defined on an order 6 triangulation.

Source Code:

• contour.f90, the source code;
• contour.csh, commands to compile and load the source code;

Examples and Tests:

• values.txt, the input file;
• node.txt, the output node file.
• element.txt, the output element file.

List of Routines:

• CONTOUR organizes data on a rectangular grid into finite element data.
• FILE_COLUMN_COUNT counts the number of columns in the first line of a file.
• FILE_LINE_COUNT counts the number of lines in a file.
• GET_UNIT returns a free FORTRAN unit number.
• GRID_Q4 produces a grid of 4 node quadrilaterals.
• GRID_SHAPE_2D guesses the shape N1 by N2 of a vector of data.
• GRID_T3 produces a grid of pairs of 3 node triangles.
• GRID_T6 produces a grid of pairs of 6 node triangles.
• PERM_CHECK checks that a vector represents a permutation.
• RVEC2_SORT_HEAP_INDEX_A does an indexed heap ascending sort of a set of (X,Y) data.
• RVEC2_UNIQUE_INDEX indexes unique elements in a sorted array of pairs of reals.
• RVEC_PERMUTE permutes a real vector in place.
• RVEC_READ reads a vector of real data from a file.
• RMAT_READ reads a matrix of real data from a file.
• TIMESTAMP prints the current YMDHMS date as a time stamp.
• WRITE_ELEMENT writes an element data file.
• WRITE_NODE writes a node data file.
• WORD_COUNT counts the number of "words" in a string.

You can go up one level to the FORTRAN90 source codes.