numpy_diag.Rmd

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## Diagonal matrices

We often want to make matrices with all zeros except on the diagonal –
diagonal matrices.

Numpy does not fail us:

```{python}
import numpy as np
np.diag([3, 4, 5, 6])
```

```{python}
np.diag([7, 8, 9, 10, 11])
```

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