How do I iterate over an array?

• 0
  I need to create a code that will calculate the potentials for solving a transport problem.
  Some of the code was created by another person as a separate task. I need to insert the equation calculation part into it.
  But an error occurs when I drive the data into an array.
  

  var klick_button = document.getElementById('ras');
  		klick_button.onclick = function() {
  
  				var cel_fun = 0;
  
  				var rows = document.getElementById("x").value,
  				columns = document.getElementById("y").value;
  				for(var i = 0; i < rows; i++){
  					for(var j = 0; j < columns; j++){
  						var value_1, value_2;
  
  						value_1 = parseInt(document.getElementById('input-' + i + "-" + j).value);
  						value_2 = parseInt(document.getElementById('input2-' + i + "-" + j).value);
  
  						cel_fun = cel_fun + (value_1 * value_2);
  
  						
  						var u=[];
  						var v=[];
  						var mat=[
  							[],
  							[],
  						];
  						n=n+1;
  						if (value_1 != 0) {
  							mat[n][0]=u[i];
  							mat[n][1]=v[j];
  							mat[n][2]=value_2;
  						}
  					}
  				}
  			alert(mat[0][2]);
  		}

  
  value_1 and value_2 are data that the user enters into the table.
  When I use mat [i] [2] during the iteration, the function works, but this is correct, since the volume should be larger for me.
  When I write mat [n] [2], the function simply does not work and does not output anything.
  Tell me what the problem is and what method is more optimal to solve a system of equations, the number of which depends on the size of the table.

  JavaScript Arya Stuart, Jan 8, 2019

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1 Answers
• 0
  If I understand correctly, then you should make the declaration of materts outside the for loop.
  
  

  var klick_button = document.getElementById('ras');
  
      klick_button.onclick = function() {
  
  
  
          var cel_fun = 0;
  
              var u=[];
  
              var v=[];
  
              var mat=[
  
                [],
  
                [],
  
              ];
  
  
  
          var rows = document.getElementById("x").value,
  
          columns = document.getElementById("y").value;
  
          for(var i = 0; i < rows; i++){
  
            for(var j = 0; j < columns; j++){
  
              var value_1, value_2;
  
  
  
              value_1 = parseInt(document.getElementById('input-' + i + "-" + j).value);
  
              value_2 = parseInt(document.getElementById('input2-' + i + "-" + j).value);
  
  
  
              cel_fun = cel_fun + (value_1 * value_2);
  
  
  
              
  
              n=n+1;
  
              if (value_1 != 0) {
  
                mat[n][0]=u[i];
  
                mat[n][1]=v[j];
  
                mat[n][2]=value_2;
  
              }
  
            }
  
          }
  
        alert(mat[0][2]);
  
      }

  Anonymous

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