OUTPUTFORMAT

When GNU Archimedes saves the various solution outputs, it have to know in which format to do it. This is specified by the user in the following way, in the input file

 OUTPUTFORMAT formattype

where formattype can be one of the following two choices

1. GNUPLOT. This sets that the output files will finish by the extension xyz which means that the file will be in the following format
   
   $$x_i \quad y_j \quad v(x_i,y_j)$$
   $$x_{i+1} \quad y_j \quad v(x_{i+1},y_j)$$
   $$x_{i+2} \quad y_j \quad v(x_{i+2},y_j)$$
   $$x_{i+3} \quad y_j \quad v(x_{i+3},y_j)$$
   $$...$$
   $$x_{N_x} \quad y_j \quad v(x_{N_x},y_j)$$
   $$...$$
   $$x_i \quad y_{j+1} \quad v(x_i,y_{j+1})$$
   $$x_{i+1} \quad y_{j+1} \quad v(x_{i+1},y_{j+1})$$
   $$x_{i+2} \quad y_{j+1} \quad v(x_{i+2},y_{j+1})$$
   $$x_{i+3} \quad y_{j+1} \quad v(x_{i+3},y_{j+1})$$
   $$...$$
   $$x_{N_x} \quad y_{N_y} \quad v(x_{N_x},y_{N_y})$$

2. MESH. The MESH format is a little bit more complex than the GNUPLOT one. In this case, we have a file which describes the mesh and another which describes the solution on that mesh.
   Concerning the mesh file, it have a file structure like the following

    MeshVersionFormatted 1
    Dimension 2
    Vertices
    number of vertices
    x1 y1 0
    x2 y1 0
    x3 y1 0
    ...
    xn y1 0
    ...
    xn yn 0
    Quadrilaterals
    number of quadrilaterals
    v1_1 v2_1 v3_1 v4_1 0
    v1_2 v2_2 v3_2 v4_2 0
    ...
    v1_N v2_N v3_N v4_N 0
   

   Concerning the file for the solution on the mesh, the file have the following structure

    2 1 number of vertices 2
    solution on the 1-st vertex
    solution on the 2-nd vertex
    solution on the 3-th vertex
    solution on the 4-th vertex
    ...
    solution on the last vertex
   

   This kind of format is becoming very popular in the scientifical computation community, that is why the author have reputed important to implement it in GNU Archimedes.