otp.Source.update#

Source.update(if_set, else_set=None, where=1, inplace=False)#

Update field of the Source or state variable.

Parameters

if_set (dict) – Dictionary <field name>: <expression>.
else_set (dict, optional) – Dictionary <field name>: <expression>
where (expression, optional) –
Condition of updating.

If where is True the fields from if_set will be updated with corresponding expression.

If where is False, the fields from else_set will be updated with corresponding expression.
inplace (bool) – A flag controls whether operation should be applied inplace. If inplace=True, then it returns nothing. Otherwise method returns a new modified object.
self (Source) –

Return type

Source or None.

Examples

Columns can be updated with this method:

>>> t = otp.Ticks({'X': [1, 2, 3],
...                'Y': [4, 5, 6],
...                'Z': [1, 0, 1]})
>>> t = t.update(if_set={'X': t['X'] + t['Y']},
...              else_set={'X': t['X'] - t['Y']},
...              where=t['Z'] == 1)
>>> otp.run(t)
                     Time  X  Y  Z
0 2003-12-01 00:00:00.000  5  4  1
1 2003-12-01 00:00:00.001 -3  5  0
2 2003-12-01 00:00:00.002  9  6  1

State variables can be updated too:

>>> t = otp.Ticks({'X': [1, 2, 3],
...                'Y': [4, 5, 6],
...                'Z': [1, 0, 1]})
>>> t.state_vars['X'] = 0
>>> t = t.update(if_set={t.state_vars['X']: t['X'] + t['Y']},
...              else_set={t.state_vars['X']: t['X'] - t['Y']},
...              where=t['Z'] == 1)
>>> t['UX'] = t.state_vars['X']
>>> otp.run(t)
                     Time  X  Y  Z  UX
0 2003-12-01 00:00:00.000  1  4  1   5
1 2003-12-01 00:00:00.001  2  5  0  -3
2 2003-12-01 00:00:00.002  3  6  1   9