# python: convert array into integer

• Last Update :
• Techknowledgy :

To convert numpy float to int array in Python, use the np.astype() function. The np.astype() function takes an array of float values and converts it into an integer array.,Numpy astype() is a typecasting function that can be cast to a specified type. For example, if you want to convert your Numpy float array to int, you can use the astype() function. To make one of these into an int, or one of the other types in numpy, use the numpy astype() method.,Numpy astype() function is relatively simple in its use is bundled along with other such utilizable functions, and we can convert from one standard data type to another data type. We have seen numpy float to int and float to a complex array. That is it for today.,So, we have converted the numpy float array to a numpy complex array using the np astype() function.

1._
```# app.py

import numpy as np

og_array = np.array([
[11.21, 19.21],
[46.21, 18.21],
[29.21, 21.21]
])
print(og_array)```

#### Output

```python3 app.py[[11.21 19.21]
[46.21 18.21]
[29.21 10.21]]```

Let’s convert float array to int array.

```# app.py

import numpy as np

og_array = np.array([
[11.21, 19.21],
[46.21, 18.21],
[29.21, 21.21]
])
print(og_array)

print('After converting numpy float array to int array')
int_array = og_array.astype(int)
print(int_array)```

See the following code.

```# app.py

import numpy as np

og_array = np.array([
[11.21, 19.21],
[46.21, 18.21],
[29.21, 21.21]
])
print(og_array)

print('After converting numpy float array to int array')
int_array = np.int_(og_array)
print(int_array)
print("The data type of int_array is: ")
print(int_array.dtype)```

Suggestion : 2

Using the numpy function astype,It is also possible to round the numbers and after convert them to integer using the numpy function around,Note: work also with the function rint, example ,Truncate the numbers first

To convert a float array to an integer array in python, a solution is to use astype, example:

```>>>
import numpy as np
>>>
A = np.array((0.4, 1.6, 2.1, -3.7, 2.9)) >>>
A
array([0.4, 1.6, 2.1, -3.7, 2.9]) >>>
A = A.astype(int) >>>
A
array([0, 1, 2, -3, 2])```

It is also possible to round the numbers and after convert them to integer using the numpy function around

```>>>
import numpy as np
>>>
A = np.array((0.4, 1.6, 2.1, -3.7, 2.9)) >>>
A
array([0.4, 1.6, 2.1, -3.7, 2.9]) >>>
A = np.around(A) >>>
A
array([0., 2., 2., -4., 3.]) >>>
A = A.astype(int) >>>
A
array([0, 2, 2, -4, 3])```

Note: work also with the function rint, example

```>>>
import numpy as np
>>>
A = np.array((0.4, 1.6, 2.1, -3.7, 2.9)) >>>
A
array([0.4, 1.6, 2.1, -3.7, 2.9]) >>>
A = np.rint(A) >>>
A
array([0., 2., 2., -4., 3.]) >>>
A = A.astype(int) >>>
A
array([0, 2, 2, -4, 3])```

### Round to the nearest bigger integer

```>>>
import numpy as np
>>>
A = np.array((0.4, 1.6, 2.1, -3.7, 2.9)) >>>
A
array([0.4, 1.6, 2.1, -3.7, 2.9]) >>>
A = np.ceil(A) >>>
A
array([1., 2., 3., -3., 3.]) >>>
A = A.astype(int) >>>
A
array([1, 2, 3, -3, 3])```

### Round to the nearest smaller integer

```>>>
import numpy as np
>>>
A = np.array((0.4, 1.6, 2.1, -3.7, 2.9)) >>>
A
array([0.4, 1.6, 2.1, -3.7, 2.9]) >>>
A = np.floor(A) >>>
A
array([0., 1., 2., -4., 2.]) >>>
A = A.astype(int) >>>
A
array([0, 1, 2, -4, 2])```

Suggestion : 3

Last Updated : 03 Dec, 2020

Examples:

```Input: [1, 2, 3]
Output: 123

Input: [55, 32, 890]
Output: 5532890```

Output:

`121517`

Suggestion : 4

Try this:

```int i, k = 0;
for (i = 0; i < n; i++)
k = 10 * k + a[i];```

Here is a function I made

```int array_to_num(int arr[], int n) {
char str[6][3];
int i;
char number[13] = {
'\n'
};

for (i = 0; i < n; i++) sprintf(str[i], "%d", arr[i]);
for (i = 0; i < n; i++) strcat(number, str[i]);

i = atoi(number);
return i;
}```

where `str[6][3]` means there are `6` elements that can hold `2` digit numbers, change it to suit your needs better. Also `n` is the size of the array you put into the function. Use it like this:

```int num[6] = {
13,
20,
6,
4,
3,
55
};
int real_num;
real_num = array_to_num(num, 6);```

try this one:

```#include <stdio.h>
#include <math.h>

int main()
{
int arr[] = {1, 2, 2, 43, 4, 27};
int size = sizeof(arr)/sizeof(arr[0]);
int n = 0;
int number  = 0;
int val  = 0;
while(n <size)
{
val = arr[n];
while(val!= 0)
{
val = val/10;
number = number*10;
}
number = number + arr[n];
n++;
}
printf("%d", number);
return 0;
}
```
1._
```#include <stdio.h>
#include <stdlib.h>

int main(int argc, char ** argv){
int n;
char buff[100];

sprintf(buff,"%d%d%d%d%d%d%d", 0, 1,2, 3, 4, 5, 6);
n = atoi(buff);

printf("the number is %d",n);

}
```

another version

```#include <stdio.h>
#include <stdlib.h>

int main(int argc, char ** argv){
int n;
int i;
char buff[100];
int x[]={0,1,2,3,4,5,6};
for (i=0; i<7; i++) {
sprintf(&buff[i],"%d",x[i]);
}
n = atoi(buff);

printf("the number is %d",n);

}
```

(note, things like negative values are not accounted for here)

```#include <ansi_c.h>
int ConcatInts(int *a, int numInts);
int main(void)
{
int a;
int m[]={1,2,3,4,5,6,7,8,9};
int size = sizeof(m)/sizeof(m[0]);

a = ConcatInts(m, size); //a = 123456789

return 0;
}

int ConcatInts(int *a, int numInts)
{
int i=0, size;
int b=0;
int mult = 1;
size = sizeof(a)/sizeof(a[0]);
for(i=0;i<numInts;i++)
{
if((a[i] < 0) ||(a[i]>9)) return -1;
if(i==0)
{
b += a[i];
}
else
{
b *= 10;
b += a[i];
}
}
return b;
}
```
```    #include <stdio.h>

char* arr2str(int arr[], int size) {
static char buffer[256];
memset(&buffer[0], 0, sizeof(buffer)/sizeof(char));
char *ptr = &buffer[0];
for(int i=0; i<size; ++i) {
sprintf(ptr += strlen(ptr), "%d", arr[i]);
}
return buffer;
}

int arr2int(int arr[], int size) {
char buffer[256] = {0,};
char *ptr = &buffer[0];
for(int i = 0; i < size; ++i) {
sprintf(ptr += strlen(ptr), "%d", arr[i]);
}
return atoi(&buffer[0]);
}

int main(int argc, const char * argv[]) {

int arr[] = {1,2,3,4,5,6,7,8,9,0};
int size = sizeof(arr) / sizeof(int);
char *str = arr2str(arr, size);
int num = arr2int(arr, size);
printf("%s, %d", str, num);
}
```

Suggestion : 5

Line 7: We use the astype() method to change the my_array array from a float type to an integer type and assign the value to a new variable called new_array., Line 7: We use the astype() method to change the my_array array from a float type to an integer type and assign the value to a new variable called new_array. ,Line 4: We use the array() method to create a float type of the array and assign it to a variable called my_array., Line 4: We use the array() method to create a float type of the array and assign it to a variable called my_array.

```from numpy
import array

# crreating the bool datatype of an array
my_array = array([1, 2, 3, 4, 5], dtype = 'f')
print(my_array)
print(my_array.dtype)```

### Syntax

`array.astype(typcode)`
```from numpy
import array

# creating a float type of array
my_array = array([3.1, 2.1, 1.5])

# converting the old array to an integer type
new_array = my_array.astype('i')

print(new_array)

# to check the data type of array we created
print(new_array.dtype)```

Suggestion : 6

how to convert a sentence into string array in java , how to convert list to integer in python , in java how to convert string to integer , how to convert array to int

```num = [1, 2, 3, 4]

s = [str(i) for i in num] # Converting integers into strings

result = str("".join(s)) # Join the string values into one string

print(result)```
```int[] nums = {
5,
1,
2,
11,
3
}; //List or Vector
Arrays.sort(nums); //Collections.sort() for List,Vector
String a = Arrays.toString(nums); //toString the List or Vector
String ar[] = a.substring(1, a.length() - 1).split(", ");
System.out.println(Arrays.toString(ar));```
`desired_array = [int(numeric_string) for numeric_string in current_array]`
```int[] arr = {
1,
2,
3
};
IntStream.of(arr).boxed().collect(Collectors.toList());```
```A = np.array((0.4, 1.6, 2.1, -3.7, 2.9)) >>>
A
array([0.4, 1.6, 2.1, -3.7, 2.9]) >>>
A = A.astype(int) >>>
A
array([0, 1, 2, -3, 2])```
```x = x.reshape(-1, 1)

# remember to check shape of your variable using x.shape,
if it shows
#(y, n) then it is already 2 D,
if it shows(y, ) instead, it is 1 D.```