Well, the error message is clear, the ticker column in at least one of your table contain a mixture of char array and non-char arrays. Let's check:
>>find(~cellfun(@ischar, identifiers.ticker))
ans =
0×1 empty double column vector
identifiers is fine.
>>find(~cellfun(@ischar, Data1.ticker), 3)
ans =
112430
112431
112432
...
141311
Indeed, there's a problem with Data1. Let's have a look at the values:
>>Data1(~cellfun(@ischar, Data1.ticker), 1:4)
ans =
77×4 table
PERMNO date SICCD ticker
______ _____ _____ ______
78830 38411 6035 [1]
78830 38442 6035 [1]
78830 38471 6035 [1]
78830 38503 6035 [1]
Well, there's your problem. The tickers are just numeric 1. You'll have to get rid of these or fix your import before the innerjoin.
As for your second question, it's not possible with matlab's join functions but it wouldn't be particularly difficult to implement yourself. One problem though:
>> unique(ceil(log10(Data1.CUSIP(~isnan(Data1.CUSIP)))))'
ans =
5 6 7 8 15
>> unique(ceil(log10(identifiers.CUSIP(~isnan(identifiers.CUSIP)))))'
ans =
3 4 5 6
So, you have cusip in Data1 that have 5, 6, 7, 8 or 15 digits in addition to many NaNs. Similarly in identifiers, they have 3, 4, 5 or 6 digits, and again there's lot of NaNs. Again, you need to look at why this does not conform to your expectations.
