Dealing with strings and numbers in a for loop.

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Hi guys,
I have
April2003 = 55;
April2004 = 279;
April2005 = 311;
.
.
.
.
April20020 = 119
How can I run a for loop that sums up all these data for me? I tried this, but it doesn't work -
for i = 2003:2020
APRIL_total = sum('April',num2str(i))
end
Can anyone please help me?
  1 Comment
Stephen23
Stephen23 on 22 Mar 2022
Edited: Stephen23 on 22 Mar 2022
"I have..." badly designed data that forces me into writing slow, complex, inefficient code when I try to access it in a loop.
The cause is forcing meta-data into the variable names.
"Can anyone please help me?"
You can help you, by not forcing meta-data into variable names. Use arrays, just like MATLAB is designed for, to store both your data (number values) and your meta-data (dates).
A TIMETABLE might be agood choice for your data:
DT = datetime([2003;2003;2004;2005;2020;2020],[1;4;4;4;1;4],1);
V = [23;55;279;311;64;119];
TT = timetable(DT,V)
TT = 6×1 timetable
DT V ___________ ___ 01-Jan-2003 23 01-Apr-2003 55 01-Apr-2004 279 01-Apr-2005 311 01-Jan-2020 64 01-Apr-2020 119
Z = groupsummary(TT,'DT','monthofyear','sum')
Z = 2×3 table
monthofyear_DT GroupCount sum_V ______________ __________ _____ 1 2 87 4 4 764

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Accepted Answer

Steven Lord
Steven Lord on 22 Mar 2022
Having variables with numbered names like this is a code smell. See this Answers post for an explanation of why they smell and alternatives you should use instead.

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