rounding numbers

I am trying to write a program which first gets a number from the user, then rounds the number to an integer, then to its 10s place, 100s place and finally its 1,000s place. Here's what I’ve got so far:

Code:

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

float        getNumber();
float        roundToInteger(float);
float        roundToTenths(float);
float        roundToHundredths(float);
float        roundToThousandths(float);

int main(){
        float        number;
        float        to_integer;
        float        to_tenths;
        float        to_hundredths;
        float        to_thousandths;

        number = getNumber();

        while(number != -1){
                to_integer = roundToInteger(number);
                to_tenths = roundToTenths(number);
                to_hundredths = roundToHundredths(number);
                to_thousandths = roundToThousandths(number);

                printf("\tnumber rounded to integer: %f\n", to_integer);
                printf("\tnumber rounded to tenths: %f\n", to_tenths);
                printf("\tnumber rounded to hundreths: %f\n", to_hundredths);
                printf("\tnumber rounded to thousandths: %f\n\n", to_thousandths);
                number = getNumber();
        }

        return 0;
}

float        getNumber(){
        float        number;

        printf("enter a number (-1 to end): ");
        scanf("%f", &number);
        return number;
}


float        roundToInteger(float number){
        return floor(number + .5);
}

float        roundToTenths(float number){
        return floor(number * 10 + .5) / 10;
}

float        roundToHundredths(float number){
        return floor(number * 100 + .5) / 10;
}

float        roundToThousandths(float number){
        return floor(number * 1000 + .5) / 10;
}

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After compiling, I get the following for output:

Quote:

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enter a number (-1 to end): 123.456789
number rounded to integer: 123.000000
number rounded to tenths: 123.500000
number rounded to hundreths: 1234.599976
number rounded to thousandths: 12345.700195

enter a number (-1 to end):

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Thank you in advance.

Code:

---


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

float        getNumber();
float        roundToInteger(float);
float        roundToTenths(float);
float        roundToHundredths(float);
float        roundToThousandths(float);

int main(){
        float        number;
        float        to_integer;
        float        to_tenths;
        float        to_hundredths;
        float        to_thousandths;

        number = getNumber();

        while(number != -1){
                to_integer = roundToInteger(number);
                to_tenths = roundToTenths(number);
                to_hundredths = roundToHundredths(number);
                to_thousandths = roundToThousandths(number);

                printf("\tnumber rounded to integer: %f\n", to_integer);
                printf("\tnumber rounded to tenths: %f\n", to_tenths);
                printf("\tnumber rounded to hundreths: %f\n", to_hundredths);
                printf("\tnumber rounded to thousandths: %f\n\n", to_thousandths);
                number = getNumber();
        }

        return 0;
}

float        getNumber(){
        float        number;

        printf("enter a number (-1 to end): ");
        scanf("%f", &number);
        return number;
}


float        roundToInteger(float number){
        return floor(number + .5);
}

float        roundToTenths(float number){
        return floor(number * 100 + .5) / 10;
}

float        roundToHundredths(float number){
        return floor(number * 1000 + .5) / 10;
}

float        roundToThousandths(float number){
        return floor(number * 10000 + .5) / 10;
}

---

>> Try Following Code
Closer.... ;)

maple23 fixed up your multiply factors. Now you just have to fix the divide factors to "re-base" the value correctly.

You will notice a small loss of precision in your printout. That's because 123.456789 can't be represented as precisely in a float as it can in a double. As a float, the debugger shows it as 123.45679.

Don't ignore your compiler warnings. Changing all your floats to double will remove the warnings and the (very small) loss of precision when dealing with 123.456789.

gg

Is this what you want?

Code:

---

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

float        getNumber();
float        roundToInteger(float);
float        roundToTenths(float);
float        roundToHundredths(float);
float        roundToThousandths(float);

int main(){
        float        number;
        float        to_integer;
        float        to_tenths;
        float        to_hundredths;
        float        to_thousandths;

        number = getNumber();

        while(number != -1){
                to_integer = roundToInteger(number);
                to_tenths = roundToTenths(number);
                to_hundredths = roundToHundredths(number);
                to_thousandths = roundToThousandths(number);

                printf("\tnumber rounded to integer: %f\n", to_integer);
                printf("\tnumber rounded to tenths: %f\n", to_tenths);
                printf("\tnumber rounded to hundreths: %f\n", to_hundredths);
                printf("\tnumber rounded to thousandths: %f\n\n", to_thousandths);
                number = getNumber();
        }

        return 0;
}

float getNumber(){
        float        number;

        printf("enter a number (-1 to end): ");
        scanf("%f", &number);
        return number;
}


float roundToInteger(float number){
        return round(number);
}

float roundToTenths(float number){
        return round(number * 10) / 10;
}

float roundToHundredths(float number){
        return round(number * 100) / 100;
}

float roundToThousandths(float number){
        return round(number * 1000) / 1000;
}

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