def check_intraday(estimate, returns, positions, transactions):
if estimate == '<STR_LIT>':<EOL><INDENT>if positions is not None and transactions is not None:<EOL><INDENT>if detect_intraday(positions, transactions):<EOL><INDENT>warnings.warn('<STR_LIT>' +<EOL>'<STR_LIT>' +<EOL>'<STR_LIT>')<EOL>return estimate_intraday(returns, positions, transactions)<EOL><DEDENT>else:<EOL><INDENT>return positions<EOL><DEDENT><DEDENT>else:<EOL><INDENT>return positions<EOL><DEDENT><DEDENT>elif estimate:<EOL><INDENT>if positions is not None and transactions is not None:<EOL><INDENT>return estimate_intraday(returns, positions, transactions)<EOL><DEDENT>else:<EOL><INDENT>raise ValueError('<STR_LIT>')<EOL><DEDENT><DEDENT>else:<EOL><INDENT>return positions<EOL><DEDENT>
Logic for checking if a strategy is intraday and processing it.

Parameters
----------
estimate: boolean or str, optional
    Approximate returns for intraday strategies.
    See description in tears.create_full_tear_sheet.
returns : pd.Series
    Daily returns of the strategy, noncumulative.
     - See full explanation in create_full_tear_sheet.
positions : pd.DataFrame
    Daily net position values.
     - See full explanation in create_full_tear_sheet.
transactions : pd.DataFrame
    Prices and amounts of executed trades. One row per trade.
     - See full explanation in create_full_tear_sheet.

Returns
-------
pd.DataFrame
    Daily net position values, adjusted for intraday movement.