Create a double variable array

The following code wont work because: I have a date1 variable array which is a double and the P_D variable seems to be a cell array. I need to set P_D to be a double variable, all numbers in the P_D variable are doubles.

Error using plot
Invalid data argument.
Error in thethird (line 54)
plot(date1, P_D(:,1))  

CODE:

    P_D(i,1)={Premium};
    P_D(i,2)= {Call};
    P_D(i,3)= {Put};
   
end
date1 = datenum(date,'yyyy-mm-dd HH:MM:SS');
plot(date1, P_D(:,1)) 
datetick('x', 'mm-dd')

[Guillaume]

P_D variable seems to be a cell array

Yes, you explecitly assigned cell arrays to it. Nothing surprising there. {Premium} puts premium in a cell array.

Not knowing what's in your cell array, it's difficult to tell you how to resolve your problem. Typically, cell arrays cannot be converted to double (because they contain something other than numbers).

[James Upton]

This answer doesnt really answer my question to be honest (no disrespect) I am asking how I set the P_D variable as a double array not a cell array. The variable only contains numbers.

[James Upton]

The answer was use cell2mat ..........

[Guillaume]

The answer was use cell2mat

In that case, the cell array was probably not needed in the first place. However, as I said, it's not possible to tell you the answer without nothing more about what it is you're putting in the cell array, ie class and size of the variables you're putting into the cell array and without fulling knowing how you're creating that cell array. It looks like it may be in a loop but you haven't provided all the relevant code.

[Walter Roberson]

Assign into a numeric array instead.

    P_D(i,1)=Premium;
    P_D(i,2)= Call;
    P_D(i,3)= Put;

[Rik]

Judging from the use of cells in the first place, I would guess either of the other parameters are not scalar doubles. If they are scalar doubles, then there is no need to add the complexity of a cell array.