MATLAB: Operations depending on the row/column

for loopif statementMATLABmatrix

I have a 339×339 matrix (f2) containing values and I need to multiply all the cells below row 170 and columns less than 170 by -1. Below is what I have so far.

for t=1:339

if t < 170

f2=f2*-1;

end

This just makes everything negative.

Thank you for your help!

Best Answer

 f2(1:169,:) = -f2(1:169,:)

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MATLAB: Matrix row/column augmentation

You can use F=a*(ones(20,20)).

MATLAB: How to repeat a code and build upon previous run’s results

Try this. I hope I understand you right.

CostsMtx=[16,18,17,20,17;25,27,29,32,28;1.5,1.6,1.7,2,1.8;50,54,56,60,57;60,63,65,68,64];
supply=[800,600,1000,400,100];
demand=[870,435,725,464,406];
mtxsz=size(CostsMtx);
%%%%%%%%%%
tmtx=CostsMtx;
res=zeros(mtxsz);
%%%%%%%%%
R=supply;
D=demand;
%repeat infinum times
while true
  x=min(tmtx(tmtx>0));
    %if there are no any x>0 then stop repeat
    if isempty(x)
      break;
    end
    [Row,Col]=find(tmtx==x);
    rm=R(1,Row);
    dm=D(1,Col);
    if R(1,Row)==0
        tmtx(Row,Col)=0;
    end
    if D(1,Col)==0
        tmtx(Row,Col)=0;
    end
    if rm<dm
        res(Row,Col)=tmtx(Row,Col)*R(1,Row);
        D(1,Col)=D(1,Col)-R(1,Row);
        R(1,Row)=0;
        tmtx(Row,Col)=0;
    end
    if dm<rm
        res(Row,Col)=tmtx(Row,Col)*D(1,Col);
        R(1,Row)=R(1,Row)-D(1,Col);
        D(1,Col)=0;
        tmtx(Row,Col)=0;
    end
  end
    %%%%%%%

Best Answer

Related Solutions

MATLAB: Matrix row/column augmentation

MATLAB: How to repeat a code and build upon previous run’s results

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