diff --git a/mapytex/calculus/core/compute/__init__.py b/mapytex/calculus/core/compute/__init__.py
index 8153ab2..093bf9c 100644
--- a/mapytex/calculus/core/compute/__init__.py
+++ b/mapytex/calculus/core/compute/__init__.py
@@ -16,6 +16,15 @@ from .minus import minus
 from .multiply import multiply
 from .divide import divide
 
+from ..MO.mo import MOnumber, MOstr
+from ..MO.fraction import MOFraction
+from ..MO.monomial import MOstrPower, MOMonomial
+
+from itertools import product
+from tabulate import tabulate
+
+MOS = [ MOnumber, MOstr, MOFraction, MOstrPower, MOMonomial ]
+
 OPERATIONS = {
         "+": add, 
         "-": minus, 
@@ -48,6 +57,31 @@ def compute(node, left_v, right_v):
 
     return operation(left_v, right_v)
 
+def compute_capacities(node):
+    """ Test an operation through all MOs 
+
+    :param operation: string which represent an (mo, mo) -> mo
+    :returns: { (motype, motype): True/False } when it's implemented
+
+    :example:
+    >>> compute_capacities("+")
+    [['+', 'MOnumber', 'MOstr', 'MOFraction', 'MOstrPower', 'MOMonomial'], ['MOnumber', True, False, True, False, False], ['MOstr', False, False, False, False, False], ['MOFraction', True, False, True, False, False], ['MOstrPower', False, False, False, False, False], ['MOMonomial', False, False, False, False, False]]
+
+    """
+    op = OPERATIONS[node]
+    lines =  [[node] + [mo.__name__ for mo in MOS]]
+    for left_mo in MOS:
+       lines.append(
+           [left_mo.__name__] + \
+           [(left_mo, i) in op.funcs for i in MOS]
+       )
+    return lines
+
+
+compute.__doc__ += "Implemented compute operations among MOs"
+for op in OPERATIONS:
+    compute.__doc__ += f"\n{tabulate(compute_capacities(op), tablefmt='grid')} \n"
+
 
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