What is the test for a finding of probable cause to issue a search warrant?

judge's finding of probable cause to issue a search warrant for clear error. United States v. Patterson, 292 F.3d 615, 625 (9th Cir.2002). Probable cause is determined by looking at the totality of circumstances. Illinois v. Gates, 462 U.S. 213, 230-31, 103 S.Ct. 2317, 76 L.Ed.2d 527 (1983). Probable cause exists if "it would be reasonable to seek the evidence in the place indicated in the affidavit." United States v. Peacock, 761 F.2d 1313, 1315(9th Cir.1985). We must find that the magistrate judge issuing the warrant had a substantial basis for determining probable cause existed. Id.