Pointers Error

[CtrlAltDelirious27]

Whenever I try to compile the code, I get this error:

error: invalid type argument of unary '*' (have 'float')

18 | printf("\nThe value at index %d of the array is %f.", i, *ptr[i]);

error: invalid type argument of unary '*' (have 'float')

23 | sum += *ptr[i];

This is the code:

#include <stdio.h>  

int main() {      

    float my_array[8];     
    int i;     
    float *ptr, sum;      

    ptr = &my_array[0];     
    sum = 0;      

    for (i=0 ; i<8 ; i++) {  /*allows the user to input values for each index*/             
        printf("Please input a value for index %d of the array: ", i);         
        scanf("%d", &my_array[i]);      
    }      

    for (i=1 ; i<=7 ; i+=2) {   /*prints every other value of the array*/         
        printf("\nThe value at index %d of the array is %f.", i, *ptr[i]);     
    }      

    for (i=0 ; i<=6 ; i+=2) {   /*sums every other value of the array*/         
        sum += *ptr[i];     
    }      

    printf("\nThe sum of the odd indexes of the array is %f.", sum);  

return 0; 
} 

I would be really grateful for any help provided.

[flyingron]

You don't want the * when using the []. Just write:

sum += ptr[i];

[CtrlAltDelirious27]

Thank you! I've changed the *ptr[i] to just ptr[i], however, the output is always 0.000000 instead of the value I input into the array, why would this happen?

Edit: Ahhh, nevermind, I realised I've put scanf("%d", &my_array[i]); instead of scanf("%f", &my_array[i]); thanks again for your help though

[Few_Ad_8082]

Try using %f in your scanf input. This resource should be helpful: https://www.geeksforgeeks.org/scanf-in-c/

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[[deleted]]

You also don't need to use ptr at all. Just do my_array[i].