Python: SyntaxError using bitwise function

Question

I am trying to create a basic bitwise function that filters out a certain subset of my data for me.

>>>heads=fits.open('datafile.fits')
>>>data=heads[1].data

Now, I need to mask out data points that are in a certain column and which are set to bit 0.

>>>ind=np.where(data['COLUMN_NAME'] & np.power(2,9) = 0)

However, this input throws the error

File "<stdin>", line 1
SyntaxError: keyword cant be an expression

The error does not give the normal ^ which shows where the error is, so I'm not sure which part of my input python is having an issue with.

Possible duplicate of [Python: SyntaxError: keyword can't be an expression](http://stackoverflow.com/questions/11633421/python-syntaxerror-keyword-cant-be-an-expression) — Andrew Li, Aug 24 '16 at 20:08
The question of `==` and `=` has been asked tons and tons of times — Andrew Li, Aug 24 '16 at 20:09

score 1 · Accepted Answer · answered Aug 24 '16 at 20:08

1

equal comparsion is ==:

ind=np.where(data['COLUMN_NAME'] & (2**9) == 0)

answered Aug 24 '16 at 20:08

Daniel

score 1 · Answer 2 · answered Aug 24 '16 at 20:09

1

Could it be because you use '=' (assignment) instead of '==' (equality) in the call to 'where'?

answered Aug 24 '16 at 20:09

BP8467

2 Answers2