Adding cCartogram package for computing cartograms

[benmaier]

Add meta.yaml for ccartogram: Python wrapper for density-equalizing cartograms

cCartogram provides Python bindings for Mark Newman's C implementation
of the Gastner-Newman diffusion-based cartogram algorithm (PNAS, 2004).

• Uses pybind11 for Python bindings
• Requires fftw for fast Fourier transforms
• BSD-3-Clause (core algorithm) + MIT (wrapper) license

Homepage: https://github.com/benmaier/cCartogram

Checklist

• Title of this PR is meaningful: e.g. "Adding my_nifty_package", not "updated meta.yaml".
• License file is packaged (see here for an example).
• Source is from official source.
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• Package does not ship static libraries. If static libraries are needed, follow CFEP-18.
• Build number is 0.
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[github-actions]

Hi! This is the staged-recipes linter and your PR looks excellent! 🚀

[conda-forge-admin]

Hi! This is the friendly automated conda-forge-linting service.

I wanted to let you know that I linted all conda-recipes in your PR (recipes/ccartogram/meta.yaml) and found some lint.

Here's what I've got...

For recipes/ccartogram/meta.yaml:

• ❌ This recipe is using a compiler, which now requires adding a build dependence on {{ stdlib("c") }} as well. Note that this rule applies to each output of the recipe using a compiler.

_{This message was generated by GitHub Actions workflow run https://github.com/conda-forge/conda-forge-webservices/actions/runs/19828646297. Examine the logs at this URL for more detail.}

[benmaier]

I am the author and willing to maintain this feedstock.

[conda-forge-admin]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipes/ccartogram/meta.yaml) and found it was in an excellent condition.