Plotting contour graphs in C/C++

[jastrebok]

Hello everybody,
I'm new here and I'm also quite new to programming but I need your advice on the subject of plotting my C outputs. In Matlab, there is a plotting function "contour". It has a great advantage. You give it a data matrix (each cell has one dedicated number)and it draws contour curves "between the cells" and makes nice smooth curves. I need it for plotting of error distribution in multilateration .

Do you have tips for the best library or external utility that could do it? (mainly MS Windows)

Thanks in advance for your response :)

Petr

[lspxy]

you could get the subject of the function "contour" in matlab.

then, modify it.

[jastrebok]

I'm not very experienced with graphic functions. Are there also other posibilities? I mean something like using some freeware utilities?

[donbock]

I'm a little confused. Is this contour being computed by a C or Matlab program?

Assuming you are using a C program to compute the coordinates of the contour ... you have a basic decision to make: either add graph-drawing capability to your program or export your data to a program you already have that is already good at drawing graphs. Have you considered emitting a comma-separated-values (CSV) file and then opening that file with Excel? Does Matlab import data?

[jastrebok]

I'm writing in C. I need to draw that data. Graph-drawing capability would be great but you've inspired me to use .csv as a "first" step. Just one question. Is there anything like contour in Excel?

[donbock]

Excel help tells me that my version (Excel 2010) supports 4 kinds of Surface Charts: 3-D surface, Wireframe 3-D surface, Contour, and Wireframe contour. Your version may vary. I don't know if any of these look like contour plots in Matlab.