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strcmp with or-condition

Asked by Max Bornemann on 15 Apr 2019
Latest activity Commented on by Ben Cunningham on 23 Apr 2019
Hello,
i have the following two tables:
Tab1=table('Size',[9 3],'VariableTypes',{'cell','double','double'},'VariableNames',{'Description','Year','Value'});
Tab1.Description(:)={'Gas','Gas','Gas','Pellets','Pellets','Pellets','Oil','Oil','Oil'};
Tab1.Year(:)=[2015,2020,2025,2015,2020,2025,2015,2020,2025];
Tab2=table('Size',[6 3],'VariableTypes',{'cell','double','double'},'VariableNames',{'Description','Year','Value'});
Tab2.Description(:)={'Wood','Wood','Wood','FW','FW','FW'};
Tab2.Year(:)=[2015,2020,2025,2015,2020,2025];
Tab2.Value(:)=[5,10,17,7,25,75];
I try the following calculation:
Tab1(strcmp(Tab1.Description,or('Gas','Oil')),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value');
The or-part seems to be the problem. I want the Value of 'FW' from Tab2 as the Value of 'Gas' and 'Oil' in Tab1. My original table is way bigger, so seperate calculations like:
Tab1(strcmp(Tab1.Description,'Gas'),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value');
Tab1(strcmp(Tab1.Description,'Oil'),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value');
are not purposeful. Maybe an if-condition with
||
could help, but i dont know how.
I will greatly appreciate any assistance.

  3 Comments

madhan ravi
on 15 Apr 2019
Explicitly state how your output should look like.
Hello madhan ravi,
the output should be the same as with the following calculation:
Tab1(strcmp(Tab1.Description,'Gas'),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value');
Tab1(strcmp(Tab1.Description,'Oil'),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value');
Table looks like:
Description Year Value
_________________________________________
'Gas' 2015 7
'Gas' 2020 25
'Gas' 2025 75
'Pellets' 2015 0
'Pellets' 2020 0
'Pellets' 2025 0
'Oil' 2015 7
'Oil' 2020 25
'Oil' 2025 75
Can someone help?

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2 Answers

Answer by Ben Cunningham on 16 Apr 2019
Edited by Ben Cunningham on 16 Apr 2019
 Accepted Answer

Generally I would recommend just writing out two lines as Adam proposed earlier.
But if you really want 'one line' with a list of strings to index then you could wrap it in a for loop :
for DescriptionIndex = {'Gas', 'Oil'}, Tab1(strcmp(Tab1.Description, DescriptionIndex),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value'); end

  5 Comments

I just have a further question, Mr. Cunningham.
Lets say i have the following tables:
Tab1=table('Size',[5 2],'VariableTypes',{'cell','double'},'VariableNames',{'Description','Value'});
Tab1.Description(:)={'Gas','Pellets','Oil','Electricity','Heatpump'};
Tab1.Value(:)=[5,10,17,7,25];
Tab2=table('Size',[7 2],'VariableTypes',{'cell','double'},'VariableNames',{'Description','Value'});
Tab2.Description(:)={'Districtheat','Coal','Gas','Pellets','Oil','Electricity','Heatpump'};
Tab3=table('Size',[4 2],'VariableTypes',{'cell','double'},'VariableNames',{'Description','Value'});
Tab3.Description(:)={'Wood','NaturalGas','HeatingOil','Heat'};
Tab3.Value(:)=[1,2,3,4];
This is the calculation i want to do:
for Sum2={'Wood','HeatingOil','Heat'}
for Sum1={'Pellets','Oil','Heatpump'}
Tab2{strcmp(Tab2.Description,Sum1),'Value'}=Tab1{strcmp(Tab1.Description,Sum1),'Value'}+Tab3{strcmp(Tab3.Description,Sum2),'Value'};
end
end
Is there a way to calculate both for-Loops at the same time? So calculation of entry 1 of Sum1 with entry 1 of Sum2 and so on.
So the 'long' way for what i want would be:
Tab2{strcmp(Tab2.Description,'Pellets'),'Value'}=Tab1{strcmp(Tab1.Description,'Pellets'),'Value'}+Tab3{strcmp(Tab3.Description,'Wood'),'Value'};
Tab2{strcmp(Tab2.Description,'Oil'),'Value'}=Tab1{strcmp(Tab1.Description,'Oil'),'Value'}+Tab3{strcmp(Tab3.Description,'HeatingOil'),'Value'};
Tab2{strcmp(Tab2.Description,'Heatpump'),'Value'}=Tab1{strcmp(Tab1.Description,'Heatpump'),'Value'}+Tab3{strcmp(Tab3.Description,'Heat'),'Value'};
Found the solution to my problem :-)
for Sum1={'Pellets','Oil','Heatpump';'Wood','HeatingOil','Heat'}
Tab2{strcmp(Tab2.Description,Sum1(1,:)),'Value'}=Tab1{strcmp(Tab1.Description,Sum1(1,:)),'Value'}+Tab3{strcmp(Tab3.Description,Sum1(2,:)),'Value'};
end
Well found!
If you are doing this mulitiple times you might consider putting this code in a nicely named function which may help it look clearer.
(Name the function something that makes sense for what you are doing - also the variables might benefit from clearer names).
e.g. At the end of your script :
function TabOut = myFunctionName (Tab1, Tab2, Tab3, Sum)
% My Function does something
for Sum1 = Sum
Tab2{strcmp(Tab2.Description,Sum1(1,:)),'Value'}=Tab1{strcmp(Tab1.Description,Sum1(1,:)),'Value'}+Tab3{strcmp(Tab3.Description,Sum1(2,:)),'Value'};
end
TabOut = Tab2;
end
Then in your script you can write :
Tab2 = myFunctionName (Tab1, Tab2, Tab3, {'Pellets','Oil','Heatpump';'Wood','HeatingOil','Heat'})

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Adam Danz
Answer by Adam Danz
on 16 Apr 2019
Edited by Adam Danz
on 16 Apr 2019

You would use ismember() to find the rows of Tab1.Description that match a list of options.
ismember(Tab1.Description, {'Gas', 'Oil'})
However, you'll find out that this matches 6 rows but the data on the right hand side of the equal sign only produces 3 rows.
What I think you're trying to do is to assign those 3 values to all rows in Tab1 that are labeled 'Gas' and to assign those 3 values to all rows labeled 'Oil', too.
Tab1(strcmp(Tab1.Description,'Gas'),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value');
Tab1(strcmp(Tab1.Description,'Oil'),'Value')=Tab2(strcmp(Tab2.Description,'FW'),'Value');

  3 Comments

Thank you Adam Danz! I think the solution of Ben Cunningham with the for loop solves my problem best.
Adam Danz
on 16 Apr 2019
Nice! Glad it worked out. My advice is to write the for-loop using separate lines rather than forcing it into a single line. It doesn't change the speed of performance - it's just more readable as separate lines.
Aye that's right.

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