Error invalid operands to binary have float and float - Исправление ошибок и поиск оптимальных решений проблем

Below is my code:

#include <stdio.h>

int main ( )   
{
    float a = 5,b = 2;    
    int c,d;    
    c = a % b;
    d = a/2;    
    printf("%dn",d);    
    return 0;
}

When I try to compile this, I get

«Invalid operands to binary %»

on the 6th line. How do I solve this?

Sourav Ghosh

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asked Nov 17, 2015 at 13:36

 c = a % b;

You can’t use float as operand to % operator.

Use fmod from math.h instead .

double a=5,b=2,c;
c=fmod(a,b);                 // it returns double

answered Nov 17, 2015 at 13:41

ameyCUameyCU

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As others have already mentioned, you’re having issue with the type of the operands for modulo operator. You need to have the operands of type int for the modulo operator.

To add some reference, quoting C11 standard, chapter §6.5.5, Multiplicative operators

[..] The operands of the % operator shall
have integer type.

answered Nov 17, 2015 at 13:52

Sourav GhoshSourav Ghosh

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You can’t use modulo (%) for float args. Maybe you want to do:

c = (int) a % (int) b;

answered Nov 17, 2015 at 13:41

pokopoko

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Modulo operator % is for use with integers, you have used floats.

You could use fmod(a,b) and #include <cmath>.

answered Nov 17, 2015 at 13:41

PandaPanda

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Are you sure it’s on the 6th line? It’s more likely to be the line that says

c = a % b;

because % only expects integer values, not floating point. You probably need to do a bit of casting if you really want a and b to be floats.

answered Nov 17, 2015 at 13:45

JonPJonP

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Источник

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
    float matrix[7][7]={{1.3,15.4,7.8,13.7,10.1,2.5,17.4},
                        {12.3,7.5,6.3,11.4,18.5,14.9,8.2},
                        {7.3,11.2,4.4,10.8,8.9,17.2,18.4},
                        {15.8,17.5,4.8,9.8,7.1,12.6,11.7},
                        {5.3,13.6,13.2,19.2,16.4,2.7,1.8},
                        {9.5,0.7,1.9,14.3,0.2,5.4,3.1},
                        {0.8,19.9,6.7,12.7,2.6,4.9,11.5}};
    float max=matrix[0][0];
    float min=matrix[0][0];
    float sclproizv;
    int imax,jmin;
    for(int i=0;i<7;i++){
        for(int j=0;j<7;j++){
            printf("%.1ft", matrix[i][j]);
            if(matrix[i][j]>max)
            {
                max=matrix[i][j];
                imax=i;
 
            }
            if(matrix[i][j]<min)
            {
                min=matrix[i][j];
                jmin=j;
            }
            sclproizv=matrix[imax,j]*matrix[i,jmin];
        }
        printf("n");
    }
    printf("Scalyarnoe proizvedenie:%.1fn", sclproizv);
    return 0;
}

Источник

If you are trying to run modulo / remainder operator like below, there are higher chances you might get an error as “error: invalid operands to binary” The solution for this error is as mentioned below.

 $ vim using_mod.c

#include <stdio.h>

int main(void) {
        float num = 11.00;
        int remainder = num % 3.0;

        if (remainder == 0) {
                printf("number is divisiblen");
        } else {
                printf("number is not divisible: Remainder = %dn", remainder);
        }
        return 0;
}

 $ gcc using_mod.c 
using_mod.c: In function ‘main’:
using_mod.c:5:22: error: invalid operands to binary % (have ‘float’ and ‘double’)
  int remainder = num % 3.0;

Solution :

The remainder operator (otherwise known as the modulo operator) % is a binary operator (i.e., takes exactly 2 operands) and operates only on integer types (e.g., short, int, long, long long, etc).

Hence, we either need to change float to int, or typecast both the values before and after % operator. like

int remainder = (int)num % (int)3.0;

The complete working program will look like as below,

 $ vim using_mod.c

#include <stdio.h>

int main(void) {
        float num = 6.00;
        int remainder = (int)num % (int)3.0;

        if (remainder == 0) {
                printf("number is divisiblen");
        } else {
                printf("number is not divisible: Remainder = %dn", remainder);
        }
        return 0;
}

Источник

Post Essentials Only Full Version
chowam01 New Member Total Posts : 1 Reward points : 0 Joined: 2020/11/18 16:10:52 Location: 0 Status: offline 2020/11/18 20:51:02 (permalink) 0 I am trying to cast float to bitwise int in C. Here’s my code snippet: write_eeprom(INDEX_CONFIG_TEMPERATURE_OFFSET_HIGH_INT, (unsigned int) (temperature_offset>>16)); write_eeprom(INDEX_CONFIG_TEMPERATURE_OFFSET_LOW_INT, (unsigned int) (temperature_offset)); I am getting the following error: error: invalid operands to binary >> (have ‘float’ and ‘int’), while trying to compile. Here, temperature_offset is a float type and I am trying to cast it as high int and low int as I am trying to save data in EEPROM in 16-bit chunks (as I am using a 16-bit microcontroller). I know that the ‘>>’ does not apply to float types. How can I fix this issue? I tried using a separate unsigned int variable called temperature_offset_int and then I used memcpy to cast the float into it. However, my MPLAB IDE displays an error message ‘unexpected token’ when I use the following: memcpy(&temperature_offset_int, &temperature_offset, sizeof temperature_offset); Does anyone know a solution to this problem? #1 pic24
ric Super Member Total Posts : 35931 Reward points : 0 Joined: 2003/11/07 12:41:26 Location: Australia, Melbourne Status: offline Re: error: invalid operands to binary >> (have ‘float’ and ‘int’) 2020/11/18 22:59:18 (permalink) 4 (1) You’re casting in the wrong place. This: (unsigned int) (temperature_offset>>16)) says «shift temperature_offset right sixteen bits, and THEN cast to an unsigned integer». You need to cast BEFORE the shift, so: ((unsigned int) temperature_offset>>16)) I also post at: PicForum To get a useful answer, always state which PIC you are using! #2
1and0 Access is Denied Total Posts : 15910 Reward points : 0 Joined: 2007/05/06 12:03:20 Location: Harry’s Gray Matter Status: offline Re: error: invalid operands to binary >> (have ‘float’ and ‘int’) 2020/11/18 23:46:34 (permalink) 5 (1) ric You need to cast BEFORE the shift, so: ((unsigned int) temperature_offset>>16)) Shifting a 16-bit int right 16 bits is not going to work as expected. #3
1and0 Access is Denied Total Posts : 15910 Reward points : 0 Joined: 2007/05/06 12:03:20 Location: Harry’s Gray Matter Status: offline Re: error: invalid operands to binary >> (have ‘float’ and ‘int’) 2020/11/18 23:52:18 (permalink) 0 chowam01 I am trying to cast float to bitwise int in C. Here’s my code snippet: write_eeprom(INDEX_CONFIG_TEMPERATURE_OFFSET_HIGH_INT, (unsigned int) (temperature_offset>>16)); write_eeprom(INDEX_CONFIG_TEMPERATURE_OFFSET_LOW_INT, (unsigned int) (temperature_offset)); I am getting the following error: error: invalid operands to binary >> (have ‘float’ and ‘int’), while trying to compile. Here, temperature_offset is a float type and I am trying to cast it as high int and low int as I am trying to save data in EEPROM in 16-bit chunks (as I am using a 16-bit microcontroller). I know that the ‘>>’ does not apply to float types. How can I fix this issue? I tried using a separate unsigned int variable called temperature_offset_int and then I used memcpy to cast the float into it. However, my MPLAB IDE displays an error message ‘unexpected token’ when I use the following: memcpy(&temperature_offset_int, &temperature_offset, sizeof temperature_offset); Does anyone know a solution to this problem? I believe you want to save the 32-bit floating point number and not just the integer part of the number. If so, use this: ((unsigned long )&temperature_offset) >> 16; ((unsigned long )&temperature_offset) & 0xFFFF; #4
ric Super Member Total Posts : 35931 Reward points : 0 Joined: 2003/11/07 12:41:26 Location: Australia, Melbourne Status: offline Re: error: invalid operands to binary >> (have ‘float’ and ‘int’) 2020/11/19 00:08:18 (permalink) ☄ Helpfulby chowam01 2020/11/23 21:02:12 2 (1) 1and0 ricYou need to cast BEFORE the shift, so:((unsigned int) temperature_offset>>16)) Shifting a 16-bit int right 16 bits is not going to work as expected. Good point. I didn’t notice which sub forum this was in, and assumed 32 bit ints. I wish everyone shifted to stdint definitions. I also post at: PicForum To get a useful answer, always state which PIC you are using! #5
1and0 Access is Denied Total Posts : 15910 Reward points : 0 Joined: 2007/05/06 12:03:20 Location: Harry’s Gray Matter Status: offline Re: error: invalid operands to binary >> (have ‘float’ and ‘int’) 2020/11/19 05:10:52 (permalink) ☄ Helpfulby chowam01 2020/11/23 21:06:27 0 ric I wish everyone shifted to stdint definitions. Agreed. This should be more efficient than my Post #4: (((unsigned int )&temperature_offset + 1)); ((unsigned int )&temperature_offset); #6
ric Super Member Total Posts : 35931 Reward points : 0 Joined: 2003/11/07 12:41:26 Location: Australia, Melbourne Status: offline Re: error: invalid operands to binary >> (have ‘float’ and ‘int’) 2020/11/19 12:23:17 (permalink) 0 Is that going to work at all when the variable is a float that is being cast to an integer??? I also post at: PicForum To get a useful answer, always state which PIC you are using! #7
1and0 Access is Denied Total Posts : 15910 Reward points : 0 Joined: 2007/05/06 12:03:20 Location: Harry’s Gray Matter Status: offline Re: error: invalid operands to binary >> (have ‘float’ and ‘int’) 2020/11/19 13:17:35 (permalink) 4 (1) ric Is that going to work at all when the variable is a float that is being cast to an integer??? You mean this? float foo; int32_t foo_int; uint16_t hiword, loword; foo = 123456.789; // 0x47F12065 foo_int = (int32_t) foo; // 123456 = 0x0001E240 hiword = (((uint16_t )&foo_int + 1)); // 0x0001 loword = ((uint16_t )&foo_int); // 0xE240 #8

Источник

#include <stdio.h>

void print_line(int index, int cents, int value)
{
    float count = (float)cents / (float)value;
    float dollar_part = (float)value / 100;
    float cents_part = (float) value % 100;
    printf("| %-2d | %9f.%02f | %5f |n", index, dollar_part, cents_part, count);
}

void coins(int cents)
{
    printf("You did not type in the correct format in terms of dollars and cents.n");
    printf("n+----+--------------+-------+n");
    printf("| #  | Denomination | Count |n");
    printf("+----+--------------+-------+n");
    print_line(1, cents, 10000);
    cents = cents % 10000;
    print_line(2, cents, 5000);
    cents = cents % 5000;
    print_line(3, cents, 1000);
    cents = cents % 1000;
    print_line(4, cents, 500);
    cents = cents % 500;
    print_line(5, cents, 200);
    cents = cents % 200;
    print_line(6, cents, 100);
    cents = cents % 100;
    print_line(7,  cents, 50);
    cents = cents % 50;
    print_line(8, cents, 20);
    cents = cents % 20;
    print_line(9, cents, 10);
    cents = cents % 10;
    print_line(10,cents, 5);
    cents = cents % 5;
    print_line(11, cents, 1);
    cents = cents % 1;

    printf("+----+--------------+-------+n");

    printf("n+----+--------------+-------+n");
    printf("| #  | Denomination | Count |n");
    printf("+----+--------------+-------+n");
    print_line(1, cents, 10000);
    cents = cents % 10000;
    print_line(2, cents, 5000);
    cents = cents % 5000;
    print_line(3, cents, 1000);
    cents = cents % 1000;
    print_line(4, cents, 500);
    cents = cents % 500;
    print_line(5, cents, 200);
    cents = cents % 200;
    print_line(6, cents, 100);
    cents = cents % 100;
    print_line(7,  cents, 50);
    cents = cents % 50;
    print_line(8, cents, 20);
    cents = cents % 20;
    print_line(9, cents, 10);
    cents = cents % 10;
    print_line(10,cents, 5);
    cents = cents % 5;
    print_line(11, cents, 1);
    cents = cents % 1;

    printf("+----+--------------+-------+n");

    printf("n+----+--------------+-------+n");
    printf("| #  | Denomination | Count |n");
    printf("+----+--------------+-------+n");
    print_line(1, cents, 10000);
    cents = cents % 10000;
    print_line(2, cents, 5000);
    cents = cents % 5000;
    print_line(3, cents, 1000);
    cents = cents % 1000;
    print_line(4, cents, 500);
    cents = cents % 500;
    print_line(5, cents, 200);
    cents = cents % 200;
    print_line(6, cents, 100);
    cents = cents % 100;
    print_line(7,  cents, 50);
    cents = cents % 50;
    print_line(8, cents, 20);
    cents = cents % 20;
    print_line(9, cents, 10);
    cents = cents % 10;
    print_line(10,cents, 5);
    cents = cents % 5;
    print_line(11, cents, 1);
    cents = cents % 1;

    printf("+----+--------------+-------+n");

}

int main(void)
{
    int dollars, cents;
    printf("Please enter total value: ");
    int n = scanf("%d.%d", &dollars, ¢s);
    if (n != 2)
    {
        printf("You did not type in the correct format in terms of dollars and cents.n");
    }
    else if (dollars < 0)
    {
        printf("You did not type in the correct format in terms of dollars and cents.n");
    }
    else if (cents < 0 || cents > 99)
    {
        printf("You did not type in the correct format in terms of dollars and cents.");
    }
    else
    {
        int total_cents = dollars * 100 + cents;
        coins(total_cents);
    }
return 0;


    printf("main()n");
}

My code looks like this. For line

float cents_part = (float)value % 100;

it gives an error

invalid operands to binary % (have ‘float’ and ‘int’)

. How do I fix this?

What I have tried:

Honestly I’m quite lost, still new to this for school.

Источник

#include <cs50.h>
#include <stdio.h>
#include <math.h>

int main (void) {
    printf ("Please enter the change owed:"); 
    float amount = GetFloat(); 

    if (amount < 0) {
        printf ("Please enter a positive integar for the change"); 
    }

    float amountInCents = round(amount * 100); 

    if (amountInCents > 25) {
     float Quater_Coins = amountInCents % 25;
     printf("Number of $0.25 coins used = %f", Quater_Coins); 
 }


}

I keep getting this error:

clang -ggdb3 -O0 -std=c11 -Wall -Werror -Wshadow    greedy.c  -lcs50 -lm -o greedy
**greedy.c:16:41: error: invalid operands to binary expression ('float' and 'float')
float Quater_Coins = amountInCents % 25;
                     ~~~~~~~~~~~~~ ^ ~~** 1 error generated. make: *** [greedy] Error 1

Cliff B

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asked Feb 7, 2016 at 19:14

The % operator only works with integers, so you’ll want to convert your float to an integer. That’s kind of the purpose of round(), to round off the float so it can be applied to an int variable.

answered Feb 7, 2016 at 19:41

FobokFobok

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Источник

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General Programming Boards
C Programming
invalid operands to binary?

12-15-2012

#1
Registered User
invalid operands to binary?
The following lines of code from a function of mine is producing the output (this is just for a couple of the error lines but its all like this):

hours_3b.c:151: error: invalid operands to binary + (have ‘float *’ and ‘float’)
hours_3b.c:153: error: invalid operands to binary + (have ‘float *’ and ‘double’)

Here is the code for the function:

Code:

if (employeeData[i].hours > STD_HOURS) { total_grossOT += employeeData[i].gross; /*Calculates sum total of gross pay */ total_OT += (employeeData[i].hours - STD_HOURS); /*Calculates sum total of OT */ total_hours += (employeeData[i].hours + employeeData[i].OT); /*Calculates sum total of hours */ } else { employeeData[i].OT = 0; total_gross += (employeeData[i].wage_rate * employeeData[i].hours); /*Calculates the sum total of gross pay */ total_hours += employeeData[i].hours; /*Calculates sum total of hours */ }

Im trying to figure out why this is happening. All of the variables being used are of type float.
Last edited by Salem; 12-15-2012 at 10:39 PM.

Reason: fixed tags
12-15-2012

#2
Lurking
Actually, let me put that a different way. Double check the type of thing that you are adding.

c = a + b;
For the best results, c, a and b should all be the same type.

And that type needs to match exactly the type in the binary + operator declaration:

Code:

type& operator + (const type& a, const type& b);

You’re going to have confusing problems if type is different in places. (Like using pointers)
Last edited by whiteflags; 12-15-2012 at 09:48 PM.
12-15-2012

#3

and the hat of int overfl

> All of the variables being used are of type float.
Your error messages beg to differ.

> hours_3b.c:151: error: invalid operands to binary + (have ‘float *’ and ‘float’)
> hours_3b.c:153: error: invalid operands to binary + (have ‘float *’ and ‘double’)
Something in each one of them is a pointer.

Did you forget a subscript.
12-16-2012

#4

Registered User

What are the types of total_grossOT, total_OT, total_hours, etc.? As was mentioned by your compiler, the one on the left-hand side is a float *, not a float. Try changing the offending line to include a pointer dereference. For example, assuming line 151 has the total_grossOT line, then you can change it to

*total_grossOT += some_float_arg;

That kind of fix should at least remove the compiler error, but it may still have the wrong logic. Pointers must be pointing to some valid memory for that type before you dereference it. If you’re just now discovering it’s a pointer, you might have forgotten to do this.