Interface refactoring

Find a design which is more intuitive and minimal.

codes/tb/test.py

+# ---
+# jupyter:
+#   jupytext:
+#     cell_metadata_filter: -all
+#     custom_cell_magics: kql
+#     text_representation:
+#       extension: .py
+#       format_name: percent
+#       format_version: '1.3'
+#       jupytext_version: 1.11.2
+#   kernelspec:
+#     display_name: base
+#     language: python
+#     name: python3
+# ---
+
+# %%
+import numpy as np
+from codes.params.test import compareDicts
+from functools import partial
+import itertools as it
+from codes.tb.transforms import kfunc2tbFFT, tb2kfunc
+
+# %%
+ndim = 2
+maxOrder = 5
+matrixSize = 5
+nK = 10
+
+keys = [np.arange(-maxOrder+1, maxOrder) for i in range(ndim)]
+keys = it.product(*keys)
+tb_model = {key : (np.random.rand(matrixSize, matrixSize)-0.5)*2 for key in keys}
+kfunc = tb2kfunc(tb_model)
+
+tb_new = kfunc2tbFFT(kfunc, nK, ndim=ndim)
+compareDicts(tb_model, tb_new)
+
+# %%