73 lines
1.2 KiB
Markdown
73 lines
1.2 KiB
Markdown
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# flat
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{:.no_toc}
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<nav markdown="1" class="toc-class">
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* TOC
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{:toc}
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</nav>
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## Top
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Questions to [David Rotermund](mailto:davrot@uni-bremen.de)
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## [numpy.ndarray.flat](https://numpy.org/doc/stable/reference/generated/numpy.ndarray.flat.html)
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```python
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ndarray.flat
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```
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> A 1-D iterator over the array.
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>
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> This is a numpy.flatiter instance, which acts similarly to, but is not a subclass of, Python’s built-in iterator object.
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```python
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import numpy as np
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a = np.arange(0, 12).reshape((4, 3))
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c = np.zeros_like(a)
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print(a)
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print()
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for i in range(0, c.size):
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c.flat[i] = a.flat[i] ** 2
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print(c)
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```
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Output:
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```python
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[[ 0 1 2]
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[ 3 4 5]
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[ 6 7 8]
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[ 9 10 11]]
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[[ 0 1 4]
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[ 9 16 25]
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[ 36 49 64]
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[ 81 100 121]]
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```
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## Reminder: size vs shape
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### [numpy.ndarray.size](https://numpy.org/doc/stable/reference/generated/numpy.ndarray.size.html#numpy-ndarray-size)
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```python
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ndarray.size
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```
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> Number of elements in the array.
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>
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> Equal to np.prod(a.shape), i.e., the product of the array’s dimensions.
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### [ndarray.shape](https://numpy.org/doc/stable/reference/generated/numpy.ndarray.shape.html#numpy-ndarray-shape)
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```python
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ndarray.shape
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```
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> Tuple of array dimensions.
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