# How to create this table/matrix?

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Manny on 22 Feb 2024
Commented: Manny on 22 Feb 2024
Hi everyone
I need to create a matrix that is the concatenation of two different sources.
First column of concatenated matrix - First 10 entries of column SYMBOL of table CIV:
CIV =
2448×3 table
_______ __________ ____________________________
{'SPX'} 7.393e+05 11.654
{'SPX'} 7.393e+05 11.337
{'SPX'} 7.393e+05 10.736
Second column of concatenated matrix - All entries of ForecastDates:
T0 = datetime(2024,02,16);
T1 = datetime(busdate(T0,1));
T2 = datetime(busdate(T1,1));
T3 = datetime(busdate(T2,1));
T4 = datetime(busdate(T3,1));
T5 = datetime(busdate(T4,1));
T6 = datetime(busdate(T5,1));
T7 = datetime(busdate(T6,1));
T8 = datetime(busdate(T7,1));
T9 = datetime(busdate(T8,1));
T10 = datetime(busdate(T9,1));
ForecastDates = [T1 T2 T3 T4 T5 T6 T7 T8 T9 T10];
I need a 10 by 2 matrix. The first column is SYMBOL and second is ForecastDates'. I did the following but I am getting an error:
>> ForecastInfo = [CIV.SYMBOL(1:10,:) ForecastDates']
Error using horzcat
Inconsistent concatenation dimensions because a 10-by-1 'double' array was converted to a 1-by-1 'cell'
array. Consider creating arrays of the same type before concatenating.
>> CIV.SYMBOL(1:10,:)
ans =
10×1 cell array
{'SPX'}
{'SPX'}
{'SPX'}
{'SPX'}
{'SPX'}
{'SPX'}
{'SPX'}
{'SPX'}
{'SPX'}
{'SPX'}
>> ForecastDates'
ans =
739302
739303
739304
739305
739308
739309
739310
739311
739312
739315
>>
Each is a 10 by 1 so it looks ok but I am not sure what I did wrong. Is someone able to help me with this?
Thank you
##### 3 CommentsShow 1 older commentHide 1 older comment
Manny on 22 Feb 2024
@Stephen23, what do you mean by class?
I need columns 1 and 2 to be different data types b/c that is how the original CIV matrix is setup. How do I do this?
Stephen23 on 22 Feb 2024
Edited: Stephen23 on 22 Feb 2024
"what do you mean by class?"
Class is basically a fancy word for the type of an array (the terms type and class are often treated as synonyms).
MATLAB has several numeric class arrays, e.g. DOUBLE, SINGLE, UINT8, etc. Numeric arrays contain numbers.
MATLAB also has container classes (which are arrays that can contain other arrays), for example CELL, STRUCT, TABLE, etc.
An array itself is just the instance of one class.
"I need columns 1 and 2 to be different data types b/c that is how the original CIV matrix is setup. How do I do this?"
Use a TABLE:

Walter Roberson on 22 Feb 2024
ForecastInfo = table(CIV.SYMBOL(1:10,:), ForecastDates', 'VariableNames', {'Symbol', 'Forcecast Dates'});
Manny on 22 Feb 2024
thank you so much! it works