What is the difference between "|" and "or"?

Question

i am using numpy :

In [83]: names = np.array(['Bob', 'Joe', 'Will', 'Bob', 'Will', 'Joe', 'Joe'])

In [93]: mask = (names == 'Bob') | (names == 'Will')

why can not I use "or" instead of "|"?

why does it give me error when I remove the pretenses in In[93] ?

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

Thanks in advance.

This information is easily findable in the documentation. – wim Jun 03 '14 at 15:41 — wim, Jun 03 '14 at 15:41
`|` is bitwise OR, `or` is logical OR – Cory Kramer Jun 03 '14 at 15:42 — Cory Kramer, Jun 03 '14 at 15:42
what is the error for in the second one? – someone Jun 03 '14 at 15:47 — someone, Jun 03 '14 at 15:47

score 2 · Accepted Answer · edited Jun 12 '14 at 12:05

2

and is python's logical-AND operator.

| is python's bitwise-OR operator (not bitwise-AND, as your question might suggest), which numpy overrides in order to make it the numpy element-wise-OR.

Numpy couldn't have overridden and nor or to work element-wise, because and and or are not overridable in python. Therefor, the bitwise operators are overridden in numpy.

edited Jun 12 '14 at 12:05

pippin1289

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answered Jun 03 '14 at 15:42

shx2

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What is the difference between "|" and "or"?

1 Answers1