cython.c

        /* "sage/matrix/matrix_generic_dense.pyx":369
 *                 m = i*snc
 *                 for k in range(snc):
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 *                 v[p] = z
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 */
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// ....

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perf.txt

+   93.99%     0.00%  python           matrix0.so                             [.] __Pyx_PyObject_CallOneArg                                                                      ◆
-   93.99%    21.32%  python           matrix_generic_dense.so                [.] __pyx_pw_4sage_6matrix_20matrix_generic_dense_20Matrix_generic_dense_15_multiply_classical     ▒
   - 72.67% __pyx_pw_4sage_6matrix_20matrix_generic_dense_20Matrix_generic_dense_15_multiply_classical                                                                           ▒
      - 27.85% PyNumber_InPlaceAdd                                                                                                                                               ▒
         - __pyx_pw_4sage_9structure_7element_7Element_71__add__                                                                                                                 ▒
              12.52% _Z98__pyx_f_4sage_5rings_12finite_rings_14element_givaro_25FiniteField_givaroElement__add___pyx_wrap_1P80__pyx_obj_4sage_5rings_12finite_rings_14element_giv▒
            - 9.21% _Z86__pyx_f_4sage_5rings_12finite_rings_14element_givaro_25FiniteField_givaroElement__add_P80__pyx_obj_4sage_5rings_12finite_rings_14element_givaro_FiniteFie▒
               - _ZL83__pyx_f_4sage_5rings_12finite_rings_14element_givaro_make_FiniteField_givaroElementP67__pyx_obj_4sage_5rings_12finite_rings_14element_givaro_Cache_givaroi ▒
                    _ZL21__Pyx_GetItemInt_FastP7_objectliii.constprop.271                                                                                                        ▒
              1.86% __pyx_f_4sage_9structure_7element_classify_elements                                                                                                          ▒
      - 20.86% __pyx_tp_getattro_4sage_9structure_7element_Element                                                                                                               ▒
         - 9.64% __Pyx_PyObject_GenericGetAttrNoDict                                                                                                                             ▒
              7.25% method_get                                                                                                                                                   ▒
              2.40% _PyType_Lookup@plt                                                                                                                                           ▒
           9.59% __Pyx_PyObject_GenericGetAttr                                                                                                                                   ▒
      - 15.28% _ZL89__pyx_pw_4sage_5rings_12finite_rings_14element_givaro_25FiniteField_givaroElement_21_mul_P7_objectS0_                                                        ▒
         - 7.89% _Z86__pyx_f_4sage_5rings_12finite_rings_14element_givaro_25FiniteField_givaroElement__mul_P80__pyx_obj_4sage_5rings_12finite_rings_14element_givaro_FiniteField_▒
            - _ZL83__pyx_f_4sage_5rings_12finite_rings_14element_givaro_make_FiniteField_givaroElementP67__pyx_obj_4sage_5rings_12finite_rings_14element_givaro_Cache_givaroi    ▒
                 _ZL21__Pyx_GetItemInt_FastP7_objectliii.constprop.271                                                                                                           ▒
           6.73% 0xcc08                                                                                                                                                          ▒
        5.38% PyNumber_InPlaceAdd@plt                                                                                                                                            ▒
        3.26% meth_dealloc                                                                                                                                                       ▒
   - 16.15% __pyx_pw_4sage_9structure_7element_6Matrix_1__mul__                                                                                                                  ▒
        __pyx_f_4sage_6matrix_7matrix0_6Matrix__matrix_times_matrix_                                                                                                             ▒
        __Pyx_PyObject_CallOneArg                                                                                                                                                ▒
      - __pyx_pw_4sage_6matrix_20matrix_generic_dense_20Matrix_generic_dense_15_multiply_classical                                                                               ▒
           1.04% meth_dealloc                                                                                                                                                    ▒
   - 5.17% __Pyx_PyObject_CallOneArg                                                                                                                                             ▒
        __pyx_pw_4sage_6matrix_20matrix_generic_dense_20Matrix_generic_dense_15_multiply_classical