Rivier Grullon

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# Understanding 2D array (with python)

## 2D Array

Two dimensional array is an array within an array inside, in this type of array the position of a data element is refered by two indices , it's represents a table with row and columns of data. An example of this can be a recolect of the temperature in a week:

• Day 1 - 11, 12, 5, 2
• Day 2 - 15, 6, 10
• Day 3 - 10, 8, 12, 5
• Day 4 - 12, 15,8, 6

In ther array this can be represented like this:

`T = [[11, 12, 5, 2], [15, 6,10], [10, 8, 12, 5], [12,15,8,6]]`

# Accesing values in a two dimensional array

How I write before for you can acces of a specific value of the array, you have to use two indices. One index referring to the parent array and other to refer the position inside the parent:

``````T = [[11, 12, 5, 2], [15, 6,10], [10, 8, 12, 5], [12,15,8,6]]

print(T[1][2])
``````

When the code above is execute the output is

`10`

To printe the entire 2d array we can use the for loop to iterate this:

``````for r in T:
for c in r:
print(c, end = " ")
print()

``````

output:

```11 12 5 2 15 6 10 10 8 12 5 12 15 8 6```

## Inserting values in the two dimensional array

We can insert new data at specific position by using the insert() method and specifying the index:

``````T.insert(2, [0,5,11,13,6])

for r in T:
for c in r:
print(c,end = " ")
print()
``````

output:

```11 12 5 2 15 6 10 0 5 11 13 6 10 8 12 5 12 15 8 6```

## Updating values in two dimensional array

We can edit the entire inner array or some specific element by reassigning the values using the array index:

```T[2] = [ 11, 9] T[0][3] = 7```

Now the array will be:

```11 12 5 7 15 6 10 11 9 12 15 8 6```

## Deleting the values in two dimensional array

We can also delete the entire inner array or some specific data using the index and the keyword del before:

`del T[3]`

The array will be:

```11 12 5 2 15 6 10 10 8 12 5```

`

Thank you for read.