Codehs 8.1.5 Manipulating 2d Arrays -

var arrayName = [[value1, value2, ...], [value3, value4, ...], ...]; For example:

var myArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]; var value = myArray[1][2]; // value = 6 Modifying an element in a 2D array is similar to accessing an element. You simply assign a new value to the element using its row and column index. Codehs 8.1.5 Manipulating 2d Arrays

var myArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]; for (var i = 0; i < myArray.length; i++) { myArray[i].push(i + 1); } // myArray = [[1, 2, 3, 1], [4, 5, 6, 2], [7, 8, 9, 3]]; Removing a column from a 2D array can be done using a similar approach. You can use a loop to iterate over each row and remove the column value. var arrayName = [[value1, value2,

for (var i = 0; i < arrayName.length; i++) { arrayName[i].splice(columnIndex, 1); } For example: You can use a loop to iterate over

for (var i = 0; i < arrayName.length; i++) { arrayName[i].push(newValue); } For example:

var myArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]; This creates a 3x3 2D array with the specified values.

arrayName[rowIndex][columnIndex] For example: